163 24 6MB
Pages [185] Year 2017
RIBA Plan of Work 2013 Guide Conservation
The RIBA Plan of Work 2013 Guides Other titles in the series: Contract Administration, by Ian Davies Design Management, by Dale Sinclair Health and Safety, by Peter Caplehorn Information Exchanges, by Richard Fairhead Project Leadership, by Nick Willars Sustainability, by Sandy Halliday and Richard Atkins Town Planning, by Ruth Reed
The RIBA Plan of Work 2013 is endorsed by the following organisations:
Royal Incorporation of Architects in Scotland
Chartered Institute of Architectural Technologists
Royal Society of Architects in Wales
Construction Industry Council
Royal Society of Ulster Architects
RIBA Plan of Work 2013 Guide
Conservation Hugh Feilden
© RIBA Publishing, 2017 Published by RIBA Publishing, The Old Post Office, St Nicholas Street, Newcastle upon Tyne NE1 1RH ISBN 978 1 85946 590 5 Stock code 83978 The right of Hugh Feilden to be identified as the Author of this Work has been asserted in accordance with the Copyright, Designs and Patents Act 1988 sections 77 and 78. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without prior permission of the copyright owner. British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library. Commissioning Editor: Elizabeth Webster Series Editor: Dale Sinclair Project Manager: Alasdair Deas Design: Kneath Associates Typesetting: Academic+Technical, Bristol, UK Printed and bound by Hobbs the Printers Ltd, UK Chapter openers: © hanoded/iStock While every effort has been made to check the accuracy and quality of the information given in this publication, neither the Author nor the Publisher accept any responsibility for the subsequent use of this information, for any errors or omissions that it may contain, or for any misunderstandings arising from it. RIBA Publishing is part of RIBA Enterprises Ltd www.ribaenterprises.com
Contents Foreword
vii
Series editor’s foreword
ix
Acknowledgements and dedication
xi
About the author
xii
About the series editor
xiii
Introduction
01
The RIBA Plan of Work 2013
08
0 Strategic Definition
13
Stage 0
1 Preparation and Brief
43
Stage 1
2 Concept Design
61
Stage 2
3 Developed Design
77
Stage 3
4 Technical Design
95
Stage 4
5 Construction
111
Stage 5
6 Handover and Close Out
125
Stage 6
7 In Use
139
Stage 7
Further reading
153
Conservation glossary
157
RIBA Plan of Work 2013 glossary
161
Index
167
v
Foreword Although largely dealing with artefacts from the past – historic buildings – the key to good conservation practice is an open, flexible approach which looks to the future. This book embodies, and advocates, this approach. Mapped to the stages in the RIBA Plan of Work 2013, the book shows how the project team – specifically the conservation architect and the design team – can work sensitively and effectively with a variety of ‘heritage assets’ (from listed buildings to scheduled ancient monuments) – not simply to ‘preserve’ them, but also to sustain and enhance them in the broadest sense. Eminently practical in approach, including guidance on managing planning permissions and the consent processes, the book emphasises throughout the value of good design, both functional and aesthetic, and the need to attend to the particularities of site and building. Buildings are part of the wider fabric of existence. Recognising their continuing value, and understanding how to maintain, renew or even reinvent them, is core to the practical measures and considerations in this book.
Ben Derbyshire President, RIBA
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Series editor’s foreword The RIBA Plan of Work 2013 was developed in response to the needs of an industry adjusting to emerging digital design processes, disruptive technologies and new procurement models, as well as other drivers. A core challenge is to communicate the thinking behind the new RIBA Plan in greater detail. This process is made more complex because the RIBA Plan of Work has existed for 50 years and is embodied within the psyche and working practices of everyone involved in the built environment sector. Its simplicity has allowed it to be interpreted and used in many ways, underpinning the need to explain the content of the Plan’s first significant edit. By relating the Plan to a number of commonly encountered topics, the RIBA Plan of Work 2013 Guides series forms a core element of the communication strategy and I am delighted to be acting as the series editor. The first strategic shift in the RIBA Plan of Work 2013 was to acknowledge a change from the tasks of the design team to those of the project team: the client, design team and contractor. Stages 0 and 7 are part of this shift, acknowledging that buildings are used by clients, or their clients, and, more importantly, recognising the paradigm shift from designing for construction towards the use of high-quality design information to help facilitate better whole-life outcomes. New procurement strategies focused around assembling the right project team are the beginnings of significant adjustments in the way that buildings will be briefed, designed, constructed, operated and used. Design teams are harnessing new digital design technologies (commonly bundled under the BIM wrapper), linking geometric information to new engineering analysis software to create a generation of buildings that would not previously have been possible. At the same time, coordination processes and environmental credentials are being improved. A core focus is the progressive fixity of high-quality information – for the first time, the right information at the right time, clearly defining who does what, when.
ix
The RIBA Plan of Work 2013 aims to raise the knowledge bar on many subjects, including sustainability, Information Exchanges and health and safety. The RIBA Plan of Work 2013 Guides are crucial tools in disseminating and explaining how these themes are fully addressed and how the new Plan can be harnessed to achieve the new goals and objectives of our clients.
Dale Sinclair October 2017
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Acknowledgements and dedication Conservation is a forward-looking activity, so this book is dedicated to the next generation, particularly Charlotte Evans and Freddie Feilden, who both helped me examine the ideas and hone the text. I hope that their enthusiasm for historic buildings continues to grow. Many people have influenced or helped me in my thinking and approach to the conservation of buildings. Clearly, my uncle Bernard Feilden, who first suggested I should be an architect, has been a major influence, together with colleagues at Feilden+Mawson, particularly Keith Darby, Alan Robson and Gordon Montague. More recently I have benefited greatly from the discussions and exchanges in the RIBA Conservation Group and with RIBA staff, notably Alex Bulford, and with the staff at RIBA Enterprises, who have steered me through my ignorance of the publishing world. Finally, thanks to all my clients, who have let me work on their amazing buildings.
xi
About the author Hugh Feilden joined King’s College Cambridge in 1971 and trained at the University of Cambridge School of Architecture. Following practical training he qualified and joined the RIBA in 1981. After working in various small practices in East Anglia he joined Feilden+Mawson, the firm founded by his uncle Sir Bernard Feilden, and became a partner in 1996. He has specialised in work to historic buildings, including Norwich Cathedral, Home House, HM Treasury, the United Kingdom Supreme Court and the Palace of Westminster, developing an interest in the strategic aspects of conservation and, in particular, the concept of long-term beneficial use as a primary means of sustaining cultural value for future generations and the way in which this relates to the periodicity and cycles of buildings and their constituent parts. Hugh is accredited by the RIBA as a Specialist Conservation Architect (SCA) and has been a member of the RIBA Conservation Group for over six years, four as chairman. He is married, with one son, and lives in Norfolk.
xii
About the series editor Dale Sinclair is AECOM’s Director, Technical Practice, Architecture responsible for EMIA. He has delivered many large-scale projects and is passionate about developing innovative and iterative interdisciplinary design processes that embrace the circular economy, new materials and modern methods of construction. He edited the RIBA Plan of Work 2013 and authored the supporting publications, including Guide to using the RIBA Plan of Work 2013 and Assembling a Collaborative Project Team. He has published a number of books on design management and is currently writing a book that looks to redefine the lead designer role for the digital age. He is the CIC BIM champion and a member of the RIBA’s Practice and Profession Committee. He regularly speaks on the RIBA Plan of Work 2013, BIM and the future of the built environment industry.
xiii
Introduction Overview This guide helps to map the approach that the project team, and specifically the conservation architect and the design team, can take when dealing with historic buildings, with an emphasis on managing the effect of the heritage protection measures that currently apply to ‘designated assets’, such as listed buildings, buildings in a conservation area and scheduled monuments. Each case and situation will be different and the approach to apply will depend on whether the site and buildings are in stable, beneficial use or at a point of challenge or major change. There is no single set of hard and fast rules – it is more important to adopt an attitude of respect for the past, based on an understanding of what remains, and to maintain an open-minded approach to the variety of opportunities and problems that will be encountered. The guide is aligned with the stages in the RIBA Plan of Work 2013. For many projects this sequence will correspond with the definition and development of the scheme. However, some projects, especially smaller ones or those involving work during Stage 7, will have a different sequence or emphasis and readers will need to pick and choose sections as appropriate. Good conservation practice comes from an open, flexible and forward-looking approach, based on an informed understanding of the site and buildings.
Context All artists draw consciously or subconsciously on the work of previous generations for examples and inspiration. For architects, that work is most clearly expressed by the surviving historic buildings, and the skill set involved in understanding and managing changes to these buildings is broadly described as ‘conservation’. 01
RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
This use of the word has different nuances when applied to nature, archaeology and historical artefacts. Conservation can be defined in many ways, and each definition depends on a proper understanding and acknowledgement of context. This is worth bearing in mind, because a different emphasis can alter how one interprets legislation and advice. Although they surely have much in common, the care of an object in a museum context, the treatment of an archaeological find and the conservation of buildings are not identical. Indeed, it is only since the midnineteenth century that the conservation of buildings has been seen as a distinct activity. Although it has developed significantly since then as a field of architectural practice, the methods and philosophy of conservation remain subject to lively debate and discussion. There is, however, a degree of consensus among those involved with the conservation of buildings, as indicated by the various statements and charters that exist, such as the Burra Charter 1979 (reissued in 2013). These have been condensed into a set of guidelines issued by the International Council on Monuments and Sites (ICOMOS); a useful summary can be found in table 1. The 2013 Burra Charter defines conservation in its broadest sense as: all the processes of looking after a place so as to retain its cultural significance. This is intended to define conservation for a broader set of assets than just buildings and so needs further clarification. What distinguishes the conservation of buildings from that of monuments, archaeological finds and museum objects is that buildings are tools in active use. In order to protect them, they have to be maintained, updated and periodically renovated, so a degree of change is inevitable. The core of successful conservation of buildings is: the management of change in a sustainable manner to pass on cultural value to future generations. 02
INTRODUCTION
Table 1 ICOMOS guidelines SKILLS REQUIRED WHEN WORKING WITH HISTORIC BUILDINGS
a
Read a monument, ensemble or site and identify its emotional, cultural and use significance
b
Understand the history and technology of monuments, ensembles or sites in order to define their identity, plan for their conservation and interpret the results of this research
c
Understand the setting of a monument, ensemble or site, their contents and surroundings, in relation to other buildings, gardens or landscapes
d
Find and absorb all available sources of information relevant to the monument, ensemble or site being studied
e
Understand and analyse the behaviour of monuments, ensembles and sites as complex systems
f
Diagnose intrinsic and extrinsic causes of decay as a basis for appropriate action
g
Inspect and make reports intelligible to non-specialist readers of monuments, ensembles or sites, illustrated by graphic means such as sketches and photographs
h
Know, understand and apply UNESCO conventions and recommendations and ICOMOS and other recognised Charters, regulations and guidelines
i
Make balanced judgments based on shared ethical principles, and accept responsibility for the long-term welfare of cultural heritage
j
Recognise when advice must be sought and define the areas of need of study by different specialists, eg wall paintings, sculpture and objects of artistic and historical value and/or studies of materials and systems
k
Give expert advice on maintenance strategies, management policies and the policy framework for environmental protection and preservation of monuments and their contents, and sites
l
Document works executed and make same accessible
m
Work in multi-disciplinary groups using sound methods
n
Work with inhabitants, administrators and planners to resolve conflicts and to develop conservation strategies appropriate to local needs, abilities and resources
While legislation and guidance do recognise that the essence of conserving a building is to keep it in use, many people, some architects included, do not realise that simply being unoccupied can be enough to put a designated building at risk. At present 03
RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
there is not sufficient theoretical or legislative distinction between the conservation approaches required during different periods of a building’s life cycle, namely the difference between when it is simply in use and those periods when major works are inevitable (such as reroofing or the replacement of mechanical and electrical systems) or when the use of the building is challenged. Architects tend to be more involved with buildings at those points where major work is required, when their design skills will be more valuable than during operational and maintenance periods. There are three grades of listing for designated buildings in England and Wales, which it has been estimated total approximately 500,000 buildings (some list entries cover more than one building): Grade I: buildings of exceptional interest Grade II*: particularly important buildings of more than special interest Grade II: buildings that are of special interest. Listed buildings account for approximately 2% of English building stock. In March 2010, there were roughly 374,000 list entries, of which 92% were Grade II, 5.5% were Grade II* and 2.5% were Grade I. Places of worship play an important role in the UK’s architectural heritage. England alone has 14,500 listed places of worship (4,000 Grade I, 4,500 Grade II* and 6,000 Grade II), 45% of all Grade I listed buildings are places of worship. Within our current legislative and operational frameworks, conservation is seen as an area of specialisation. Accreditation schemes, such as that run by the RIBA (see figure 1), clearly show how an architect’s skill set must develop proportionally in response to the complexity of conservation required. The RIBA accreditation scheme requires demonstrable practical experience of these skills 04
INTRODUCTION
Scheduled monuments Listed buildings – Grade I and II* Listed buildings – Grade II
CR
CA
SCA
Pre-1919 general building stock
CR = Conservation Registrant CA = Conservation Architect SCA = Specialist Conservation Architect
Figure 1 RIBA Conservation Register
over a period of four to five years, with three levels of accreditation available (most other schemes only have one level). What is clear is that an architect’s design skills, creativity and experience are key to successful conservation, mediating and balancing conflicting interests with the ultimate goal of producing the best possible result for both the building and its users. Conservation skills and experience are relevant to all stages of the RIBA Plan of Work, with particular emphasis on managing the planning permission and listed building consent processes when the use and form of buildings and their sites face frequent challenges. There will also be periodic work for architects during Stage 7 when the building is in use and the emphasis will be more on appropriate management, maintenance and repair than making major changes.
How to use this book This guide will be valuable to anyone involved with and working on historic buildings and, in particular, those involved with architectural conservation. Its purpose is to outline activities and tasks specific to each stage of the RIBA Plan of Work 2013 in what should be a logical and progressive sequence. However, when 05
RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
working with historic buildings, investigation and understanding of the fabric will rarely be complete until work starts on site and the core fabric of the building is open for inspection. This means that more time must be reserved for inspecting the building during the construction period than would be the case for a new build, and there has to be a greater readiness to review earlier analysis and decisions in the light of what is revealed during construction. The reader may occasionally need to work backwards through the book! Old buildings are full of surprises. This guide can be used on its own or in conjunction with the other titles in the RIBA Plan of Work 2013 Guides series, as well as other RIBA publications such as the RIBA Job Book. In particular, there will be a significant crossover with the guides on town planning and sustainability, and while the approaches taken will generally be similar there are specific emphases to consider when dealing with designated assets such as listed buildings, and in particular the effect of legislative control over their fabric and settings. For newcomers to conservation work, the reading list for the RIBA Conservation Course (see the further reading section) will give a more thorough grounding in the subject, and for technical advice the Historic England guides are a reliable starting point, with much information available online through the Heritage Gateway website.
Hugh Feilden September 2017
06
INTRODUCTION
Using this series For ease of reference each book in this series is broken down into chapters that map on to the stages of the Plan of Work. So, for instance, the first chapter covers the tasks and considerations around Conservation at Stage 0. We have also included several in-text features to enhance your understanding of the topic. The following key will explain what each icon means and why each feature is useful to you: The ‘Example’ feature explores an example from practice, either real or theoretical
The ‘Tools and Templates’ feature outlines standard tools, letters and forms and how to use them in practice
The ‘Signpost’ feature introduces you to further sources of trusted information from books, websites and regulations
The ‘Definition’ feature explains key terms in this topic area in more detail
The ‘Hints and Tips’ feature dispenses pragmatic advice and highlights common problems and solutions
The ‘Small Project Observation’ feature highlights useful variations in approach and outcome for smaller projects
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RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
Stages
The RIBA Plan of Work 2013 organises the process of briefing, designing, constructing, maintaining, buildingthe projects a The operating RIBA Plan ofand Workusing 2013 organises process into of briefing, desi into acontent number of stages.may The content stages may vary or ove number of key stages. The ofkey stages vary orofoverlap to suit should be used solely as guidance for the preparation of detailed p specific project requirements.
0
1
2
3
Strategic Definition
Preparation and Brief
Concept Design
Developed Design
Core Objectives
Identify client’s Business Case and Strategic Brief and other core project requirements.
Develop Project Objectives, including Quality Objectives and Project Outcomes, Sustainability Aspirations, Project Budget, other parameters or constraints and develop Initial Project Brief. Undertake Feasibility Studies and review of Site Information.
Prepare Concept Design, including outline proposals for structural design, building services systems, outline specifications and preliminary Cost Information along with relevant Project Strategies in accordance with Design Programme. Agree alterations to brief and issue Final Project Brief.
Prepare Developed Design, including coordinated and updated proposals for structural design, building services systems, outline specifications, Cost Information and Project Strategies in accordance with Design Programme.
Procurement
Initial considerations for assembling the project team.
Prepare Project Roles Table and Contractual Tree and continue assembling the project team.
Tasks
*Variable task bar
Programme
Establish Project Programme. Review Project Programme.
The procurement a givendoes stage. The procurement strategy notHowever, fundamentally al strategy does not of the design or theInformation level of detailExchanges prepared at a give fundamentally alter Exchanges will vary depending on on thethe se Information will vary depending the progression the selectedAprocurement route route andofBuilding Contract. bespoke RIBA Plan o design out or the andand Building Contract. A thelevel specific tendering procurement activities th of detail prepared atstage in relation bespoke RIBA Plan procureme of Work to the chosen Review Project Programme.
*Variable task bar
(Town) Planning
Pre-application discussions.
Pre-application discussions.
*Variable task bar
Suggested Key Support Tasks
Review Feedback from previous projects.
Prepare Handover Strategy and Risk Assessments. Agree Schedule of Services, Design Responsibility Matrix and Information Exchanges and prepare Project Execution Plan including Technology and Communication Strategies and consideration of Common Standards to be used.
The procurement The procurementroute route ma may dictate the Project stages overlapping or bei Programme result in 2013and will clarify the s certain stages the overlapping specific s
Planning applications are typically made using the A bespoke Planning applications bespoke RIBA Plan Work identify RIBAofPlan of2013 Workwill 2013 will w are typicallyAmade using identify when is the the Stage 3 output. application to be made. Prepare Sustainability Strategy, Maintenance and Operational Strategy and review Handover Strategy and Risk Assessments.
Review and update Sustainability, Maintenance and Operational and Handover Strategies and Risk Assessments.
Undertake third party consultations as required and any Research and Development aspects.
Undertake third party consultations as required and conclude Research and Development aspects.
Review and update Project Execution Plan.
Review and update Project Execution Plan, including Change Control Procedures.
Consider Construction Strategy, including offsite Review and update fabrication, and develop Health Construction and Health and and Safety Strategy. Safety Strategies.
Sustainability Checkpoints
Sustainability Checkpoint — 0
Sustainability Checkpoint — 1
Sustainability Checkpoint — 2
Sustainability Checkpoint — 3
Information Exchanges
Strategic Brief.
Initial Project Brief.
Concept Design including outline structural and building services design, associated Project Strategies, preliminary Cost Information and Final Project Brief.
Developed Design, including the coordinated architectural, structural and building services design and updated Cost Information.
Not required.
Required.
Required.
Required.
(at stage completion)
UK Government Information Exchanges
*Variable task bar – in creating a bespoke project or practice specific RIBA Plan of Work 2013 via www.ribaplanofwork.com a specific bar is selected from a number of options.
08
INTRODUCTION
The RIBA Plan of Work 2013 should be used solely as guidance for the preparation of detailed professional services contracts and gning, constructing, maintaining, operating and using building projects lap to suit specific project requirements. The RIBA Plan of Work 2013 building contracts. ofessional services contracts and building contracts.
www.ribaplanofwork.com www.ribaplanofwork.com
4
5
6
7
Technical Design
Construction
Handover and Close Out
In Use
Prepare Technical Design in accordance with Design Responsibility Matrix and Project Strategies to include all architectural, structural and building services information, specialist subcontractor design and specifications, in accordance with Design Programme.
2013 will set out the er the progression tendering and nspecific stage. However, procurement activities that lected procurement occur at will each fwill Work 2013 setstage in will relation chosen at occurtoatthe each route. ntprocurement route.
Offsite manufacturing and Handover of building and onsite Construction in conclusion of Building accordance with Construction Contract. Programme and resolution of Design Queries from site as they arise.
Administration of Building Contract, including regular site inspections and review of progress.
Undertake In Use services in accordance with Schedule of Services.
Conclude administration of Building Contract.
beingthe undertaken Programme yordictate Project ProgrammeThe and Project may result in certain A bespoke A bespoke will set outPlan the specific gconcurrently. undertaken concurrently. RIBA of Work RIBAoverlaps. Plan of Work 2013 will stage dates and e stage The Project Programme will set outdetailed clarify theand stage overlaps. programme age dates detailed programme durations. durations. Stage 3 output. planning application hen is tothe beplanning made. Review and update Sustainability, Maintenance and Operational and Handover Strategies and Risk Assessments. Prepare and submit Building Regulations submission and any other third party submissions requiring consent. Review and update Project Execution Plan. Review Construction Strategy, including sequencing, and update Health and Safety Strategy.
Review and update Sustainability Strategy and implement Handover Strategy, including agreement of information required for commissioning, training, handover, asset management, future monitoring and maintenance and ongoing compilation of ‘Asconstructed’ Information.
Carry out activities listed in Handover Strategy including Feedback for use during the future life of the building or on future projects. Updating of Project Information as required.
Conclude activities listed in Handover Strategy including Post-occupancy Evaluation, review of Project Performance, Project Outcomes and Research and Development aspects. Updating of Project Information, as required, in response to ongoing client Feedback until the end of the building’s life.
Update Construction and Health and Safety Strategies.
Sustainability Checkpoint — 4
Sustainability Checkpoint — 5
Sustainability Checkpoint — 6
Sustainability Checkpoint — 7
Completed Technical Design of the project.
‘As-constructed’ Information.
Updated ‘As-constructed’ Information.
‘As-constructed’ Information updated in response to ongoing client Feedback and maintenance or operational developments.
Not required.
Not required.
Required.
As required.
© RIBA
09
RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
Stages
Conservation overlay
Tasks
0
1
2
3
Strategic Definition
Preparation and Brief
Concept Design
Developed Design
Identify the spirit of the place
Identify heritage receptors
Complete the heritage statement/ conservation plan
Scope the heritage assets on and around the site
Build an understanding of the site and buildings from readily available sources
Draft a heritage statement and decide whether this will be developed into a conservation plan
Advise on the Project Programme and risk implications if assets are present Advise on possible sources of grant aid and the potential consequences of using this type of funding
Draft a statement of significance for discussion Identify surveys and research likely to be needed Initial advice on procurement route Measured survey of site and buildings
Draft an impact assessment Carry out non-intrusive surveys and undertake research
Heritage impact assessment for planning/listed building/scheduled ancient monument consents Review specialist reports and input
Advise on specialist Write a design and involvement and input access statement based on the above Build and populate a BIM model if required Applications for listed building consent are normally made at the Identify hazardous end of this stage materials Advise on design detailing and specification Identify relevant specialist suppliers and supply chain
10
INTRODUCTION
4
5
6
7
Technical Design
Construction
Handover and Close Out
In Use
Assess planning and listed building consent conditions and programme their clearance
Update the heritage statement/ conservation plan as the building is opened up
Complete the heritage statement/ conservation plan for handover to client/ users
Clear conditions identified as pre-commencement of works
Check compliance with listed building consent conditions
Lodge completed statement/plan in a public record
Respond to discoveries on site
Confirm compliance with listed building consent conditions
Detail design and specification, working with specialist suppliers and supply chain Procurement of specialist input Salvage and protection packages Set up recording protocols and agree level of detail
Engage with specialist suppliers and supply Record discoveries chain and any hazardous materials found Monitor salvage and protection Advise on stocking of spares and maintenance items Record site and discoveries Check reinstatement after removal of protection measures Complete the record of the works
Develop the conservation plan into a conservation management plan Review the conservation plan every 5 years Carry out quadrennial/ quinquennial inspections of listed buildings Advise on maintenance and repair Advise on heritage protection agreements Review effects of changes in legislation Record the building and works carried out as the opportunity arises Be a ‘friend to the building’ Maintain the spirit of the place
11
Stage 0
Strategic Definition
13
RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
Chapter overview This chapter looks at the input that may be required from a conservation viewpoint in defining the strategy for a project. The principal activity is to identify the existence of any heritage assets, establish whether or not they are designated (for buildings this usually involves determining whether are they listed) and gain an overview of their quality or significance. In the case of buildings or built sites, it is also important to identify whether the assets are at a point of challenge or major change (the presumption being that they are if a project is being considered) and to outline opportunities for sustaining and enhancing the heritage elements and determine whether or not any harm that may arise from the proposals can be balanced by a greater public good. For buildings, a key concept is that of beneficial use. The approach taken to a building in use, which can be regarded as a functional tool, will differ from that taken when dealing with a museum artefact, an archaeological find or other heritage assets which no longer have a function. Beneficial use is defined as a use for a building which generates the resource stream necessary to sustain that building and its significance in good order for the next generation. This will inevitably require change, and conservation is the effective management of that change. The key coverage in this chapter is as follows: Identifying heritage assets (not just buildings) on and near sites being considered Finding out if they are designated (for buildings this generally means whether they are listed) Outlining the potential impact of any heritage assets on the project and its business case Identifying the impact of the heritage assets on the Strategic Brief, such as opportunities to sustain and enhance the site and buildings 14
STAGE 0: STRATEGIC DEFINITION
Introduction Stage 0 can be very important in alerting clients and other members of the team to the presence of heritage assets in the broadest sense. There will be need to carry out investigations to find assets that may be present but have not yet been identified and to advise on the general impact of the presence of heritage assets on the project as a whole. In particular, this stage provides a good opportunity to set sensible time scales and budgets in the outline Business Case, allowing for investigative work and discussion with bodies such as the local planning authority and Historic England. It will be much more disruptive if these constraints are only recognised during a later stage.
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RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
What are the Core Objectives of this stage? The Core Objectives of the RIBA Plan of Work 2013 at Stage 0 are:
0 Strategic Definition Tasks Tasks
Core Objectives
Identify client’s Business Case and Strategic Brief and other core project requirements.
The presence of heritage assets on or even near a site will have an impact on: I I I I
the client’s Business Case and Strategic Brief the Project Programme, which will tend to be longer the cost, which may be greater the risk, which will be more diverse.
There are also specific legal and planning requirements relating to heritage assets, vast quantities of advice notes to be aware of and interactions with other legislation, such as inclusive access, to be kept in mind. The key advice from a conservation perspective will be to identify heritage assets and to assess their relative significance and sensitivity at a high level so that any changes or development can be directed to locations where they will have least impact.
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STAGE 0: STRATEGIC DEFINITION
Building life cycles and times of challenge Buildings in use are regularly challenged by changing conditions and circumstances (such as the legislation governing inclusive access) as well as the life cycles of their component parts, such as mechanical, electrical and plumbing (MEP) systems and roof coverings. Factors such as missed maintenance cycles, rapid changes in use or reaching the point of redundancy can create conditions where the building is seen as no longer viable or just too difficult to keep. These points of major challenge require a different approach to the conservation of the building to that which would be usual when a building is in use and cared for, and it may be that radical solutions are required which would not normally be considered. It is important when assessing a historic building to be aware of such life cycles and the extent to which they are combining to create a challenge. Note: experience shows that a heritage statement or conservation plan written during a period of established and unchallenged use will read quite differently to one prepared at a time of challenge when a major project or intervention is being contemplated, although theoretically this should not be the case.
What are the key conservation project questions you need to ask at this stage? There are certain questions which should be asked at this stage of a project: I Can you identify the heritage assets on or near the site or that are likely to be affected by the project being considered? I What is their importance or significance and are they specifically protected? I How will they affect the project, in particular the client’s Business Case and Strategic Brief? I Will the project sustain and enhance the heritage assets that may be affected? I Can the Strategic Brief be amended to minimise any adverse impact?
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RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
What is a heritage asset? A heritage asset is a part of the historic environment that is valued because of its historic, archaeological, architectural, artistic or social interest. Heritage assets include scheduled ancient monuments, nationally listed buildings, locally listed buildings, conservation areas, parks and gardens, battlefields and archaeological finds. Many heritage assets are not buildings and it may be necessary to bring in other specialists to advise on them. How to identify heritage assets on or near the site The Heritage Gateway website (www.heritagegateway.org.uk) should show all designated assets on or near the site. Typically, the project review area or scope will be 0.5 to 1km around the site but may be up to 5km, and occasionally more, such as when tall structures are involved or proposed. There will also be information in the local historic environment record (HER). HERs are currently administered by the local county council archaeologists, and they were originally conceived as archaeological research databases. They are not specifically designed to inform or aid other users, nor are they necessarily kept up to date. This means that ease of access and quality of content can vary, particularly when council resources are scarce. If they are not readily available online, then it will be necessary to contact the local records office or the county archaeologist in order to find the necessary information or approach the local conservation officer. Where a site lies across a county boundary, both HERs will have to be consulted. It is important to identify heritage assets so that an assessment can be made of any impacts that the project may have on the assets, and in particular an assessment of their setting when they are near but outside the project site. Failing to include an asset will undermine the design team’s credibility and has the potential to necessitate major change when the asset is subsequently identified, so the identification of heritage assets is an important aspect of setting out the Business Case and building the Strategic Brief.
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STAGE 0: STRATEGIC DEFINITION
How do I find out if a particular building is listed? The best approach is to find its postcode or, more accurately, its National Grid reference and search the Historic England website (Heritage Gateway) or search the local county council historic environment record (HER) if it is available online, which some are not, or go to the local county records office. If all else fails, ask the local planning authority, as they have a duty to tell you, but you may not always get a quick reply.
How do I find out which buildings nearby are listed? If the county HER is map based and available online, it will usually show all designated assets (listed buildings, scheduled monuments, designated parks and gardens, battlefields and archaeological finds etc.) up to 1km around an identified site or building. However, if it is not map based, or is not working (a not uncommon situation) or you need a wider search diameter, you will probably have to ask the county archaeologist, local records office or local planning authority. You may have to pay for the search, particularly if it is over a wide area, and it may take time to get a response. If the site is in a conservation area there should be a conservation area assessment published by the local planning authority, which identifies all designated assets within the conservation area itself. Check what is available online before giving a fee quote for this work, and find out whether or not the county archaeologist, local planning authority or records office will make a charge if the information is not already online and has to be assembled.
Identifying heritage receptors Start with a search on the Heritage Gateway website to discover where the heritage assets are located in your selected area (Figure 0.1). Those assets within a defined scope area and which may be affected by changes to the site or building being worked on are, in current jargon, called ‘heritage receptors’. In most cases receptors will not be directly or physically
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RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
Figure 0.1 Screenshot of Heritage Gateway search results. © Historic England. © Crown Copyright and database right 2017. All rights reserved. Ordnance Survey Licence number 100024900
affected, but their setting might be. This sort of study is mostly used for large developments or where an environmental impact assessment is going to be required, in which case it is a method of agreeing the scope area of the assessment. Following the search on Heritage Gateway, on a map of the area mark each asset with an identifying number, noting each location to be added to a table of receptors (Figure 0.2). Finally, create a table of the mapped assets, colour coding heritage receptors and noting the name, designation and reason for classification (Table 0.1).
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STAGE 0: STRATEGIC DEFINITION
Defence Statue 86
85
90 79
80
83 91
78
81 74 73 72
69
64 65 67
68
07 WESTMINSTER ABBEY AND PARLIAMENT 06 SQUARE CONSERVATION AREA
08 05
66 69
58
01
03 56
Palace of Westminster
10
57
11
12
02
55
54 WESTMINSTER ABBEY AND PARLIAMENT SQUARE 53 CONSERVATION AREA 49 52 51 50 45 48 47
15
13 14
16 18
17
105
CA38 SOUTH BANK CONSERVATION AREA 104
09
04
County Hall
WHITEHALL 93 CONSERVATION AREA Statue
76
71
BIRDCAGE WALK CONSERVATION AREA 63 61 60 59
77
75
Westminster Pier
Albert Emba
70
Victoria
82
War meml
nkment
84
River Thames
89 88 87
Embank ment
ST JAMES PARK CONSERVATION AREA 92
96 Royal Dover House United Service 94 Institution 95 Ministry of
Black Rod's Steps
19b
CA10 LAMBETH PALACE CONSERVATION AREA 103 St Thomas’ Hospital
19a
44 102
41 44a
46
34 NOT A CONSERVATION 33 AREA 32
43 40 42 35
39 38 22 37 36
21
31 30
19
20a
101
20 29 28
25 27 SMITH SQUARE CONSERVATION AREA 24 26
23 100
Figure 0.2 Map of heritage receptors
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RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
Table 0.1 Tabulated results of colour-coded heritage receptors identified from map Receptor Partial receptor Not a receptor ID
LIST ENTRY NO
01
1226284
02
DESIGNATION
RECEPTOR Y/N
REASON
Palace of Westminster
grade I
yes
adjacent
1000095
World Heritage Site
World Heritage Site
yes
adjacent
03
1291494
Westminster Abbey
grade I
yes
setting
04
1226286
St Margaret’s Church
grade I
yes
setting
05
1001342
Parliament Square
registered park/garden II
yes
adjacent
Westminster Abbey CA
conservation area
yes
part of the area
06
NAME
07
1066172
Westminster Bridge
grade II*
no
not affected
08
1265947
Palace of Westminster railings
grade I
no
not affected
09
1226285
Statue of Oliver Cromwell
grade II
no
not affected
10
1225624
Statue of Richard I
grade II
no
not affected
11
1225528
Statue of George V
grade II
no
not affected
12
1003579
Chapter House
scheduled monument
yes
setting
13
1266309
6/7 Old Palace Yard
grade II*
yes
setting
14
1225529
Jewel Tower
scheduled monument
yes
setting
14A
1266310
Walls to moat
grade I
yes
setting
15
1357234
Clerk of works office and other remains
grade I
yes
setting
16
1357235
Abbey precinct wall
grade I
yes
setting
17
1430343
Statue by Henry Moore
grade II*
yes
setting
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STAGE 0: STRATEGIC DEFINITION
Map regression This is a very powerful technique, made much easier by the ready availability of old maps online. The principle is to obtain as many old maps of your site and its surroundings as possible and compare them to identify changes, working back from the present day to the earliest map you can find. This is an easy exercise when using the Ordnance Survey series which, depending upon location, can take you back to the early nineteenth century. Other sources include published maps, tithe maps and enclosure maps, which can generally be found in the local records office. Other interesting sources of information for comparison include maps produced for railway construction, Second World War bomb damage maps, estate maps etc. A well-run HER will have a number of these maps available, but do check the copyright position before publishing an image obtained online. It should also be borne in mind that maps are not infallible and are often made with a particular purpose in mind. It is quite possible that they represent the views of a biased cartographer and therefore their accuracy should not be accepted unconditionally.
Historic aerial photography Aerial photography and photographic interpretation were developed during the First World War. O.G.S. Crawford invented aerial archaeology in the 1920s, when he demonstrated the effectiveness of using these technique at Stonehenge. The Luftwaffe took large numbers of aerial photographs of the UK during the Second World War and the RAF photographed most of England in 1946. Both sets of records are available online, but, as with maps, it is essential to check the copyright position. There are gaps in the RAF’s 1946 set and, in the same way that large blank spaces appear on post-Second World War Ordnance Survey maps, these can indicate sites of military or other sensitive use.
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RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
Are there undesignated assets which will not show up on the HER? It is sensible to advise the client of the possible existence of undesignated assets which may have heritage significance as these have the potential to affect the project brief and Business Case, particularly if they are a building which is unlisted but capable of being listed, as this could have a major impact on progress through the planning system. It is becoming more common for objectors to a scheme to use a request for spot listing as a delaying tactic, and that possibility should be included in the Business Case risk register. A site visit will be required to answer this question. Despite regular listing reviews there are a surprising number of buildings which are not currently listed but which have the potential to be. Curtilage buildings and structures and buildings within the settings of listed buildings also need to be identified.
Setting Assessing, understanding and describing the setting of a listed building is a highly subjective activity. The primary advice on the subject is published by Historic England, but you should also look at advice on tall buildings and wind turbines. You will need to check local plans for any defined protected views, such as views towards St Paul’s Cathedral in London. Setting is not in itself a heritage asset unless defined by a conservation area or similar designation. In most instances, setting is largely defined by views and visibility, which can be determined fairly accurately using software such as Viewshed (available on Google Earth Pro), but the concept can also include activities (such as flying overhead), smell (for example, from a brewery), below ground archaeology (as inferred from the HER finds register) and even virtual archaeology (finds not yet known but which are believed to be present and considered potentially important). For designed buildings sitting in a designed landscape, assessing and agreeing the setting is usually straightforward, but for vernacular buildings or evolved sites, particularly in urban locations, it can be much more difficult and
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STAGE 0: STRATEGIC DEFINITION
Setting (continued ) can become increasingly subjective. This is particularly the case when assessing the setting of a nearby listed building or heritage asset which is not part of your scheme or project but whose setting may be judged to be affected by it. For large schemes requiring an environmental impact statement or assessment these issues should be scoped and as far as possible defined at the screening stage, but for smaller projects this issue can raise its head at a very late stage, due to its subjective nature. Be very cautious of any proposal to restore an ‘authentic’ setting as this is a particularly subjective approach, full of traps for the unwary. The thinking behind the concept of setting and how it may be applied in practice is constantly changing and can have a major impact on the way proposals are developed and presented.
What is the importance or significance of heritage assets? The first thing to do is to assemble published designations of known assets (the listing descriptions for designated buildings). These will give you an idea of a given building’s significance. However, early listing descriptions are simply identifiers. Modern listing descriptions will have a photograph and an overview of the history and significance of the building, but no listing description provides a complete catalogue of every aspect of interest and value and the definition of what is of interest and value can change over time. Note that the legal effect of listing covers every part of the building. This includes all fittings attached to it and curtilage structures (if they pre-date 1948) as well as the setting of the building (which covers more than just views in and out). The purpose of the analysis in a heritage statement or conservation plan is to assign relative value to the different parts of the site/building so that any intervention can be directed to less sensitive areas.
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RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
Enabling development The best definition of enabling development is that given by Historic England in its advice note, as ‘a development which falls outside the scope of existing planning policies but which is needed to secure the future of a particular heritage asset’. The tests and conditions which surround enabling development are considerable but, essentially, the first task is to establish the ‘conservation deficit’, ie how much money is realistically needed to secure the heritage asset involved, agree that sum with the local planning authority and Historic England and then agree the amount of appropriate development that will deliver that sum. This is an expensive and time-consuming process, to be avoided if at all possible. An alternative approach that can be used when development falls within existing policy limits is to include heritage benefits or gains in both the scheme proposal and also as part of a section 106 agreement. This severs the direct relationship between the amount and nature of the development and the precise delivery of heritage benefits. In general, it is recommended that you avoid describing anything as enabling development if at all possible.
You should advise clients on the need to appoint other specialists, such as archaeologists, to report on assets outside the architect’s knowledge and experience. While an architect may be able to cover the conservation of straightforward buildings alone, the ICOMOS guidelines stress the need for teamwork among all relevant disciplines. Building up a team should involve including not only other professions, such as structural engineers and archaeologists, but also craftspeople and materials suppliers with relevant specialist experience. It is also worth checking professional and skills-based accreditation schemes and there are a number of conservation directories that can be used to find the right people.
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STAGE 0: STRATEGIC DEFINITION
Preparing a general statement of significance for the site and immediate surroundings One of the key tasks at this stage is to write a statement of significance for each listed building or other heritage asset, even though the project is only just starting. It will be developed as knowledge improves and provides the basis for discussions with regulatory authorities and external stakeholders. Note that cultural significance, usually an intangible concept, is not the same as sensitivity, which tends to be more tangible and directly related to aspects of the historic fabric.
Significance and sensitivity In recent years, there has been a big shift in thinking about conservation, from concern with the simple preservation of a building ‘as it was found’, towards the sustainment of a building’s (or heritage asset’s) cultural value. Cultural value is normally described in a ‘statement of significance’, which considers the factors usually used by Historic England when determining a building’s eligibility for listing. These factors are architectural/aesthetic significance, historic significance, technical significance and social significance, with some variation in wording depending on the asset under consideration. Whereas significance is essentially intangible, and can be seen as a social/theoretical construct, sensitivity is generally quantifiable and relates directly to the historic fabric in question. Understanding the difference is important, as fabric can be sensitive without being significant. Indeed, it can be difficult to attach significance to historic fabric specifically, except for obvious standalone items, such as memorials, fireplaces, doors etc. This is particularly true when significance is given to social or community value which attaches to the activity associated with the building (such as a local hospital) as much as to the design or technical innovation of its fabric, which may be perfectly ordinary. Sensitivity will in many cases derive from the assessment of significance, but it can also be a technical issue, such as not repointing lime mortar with a cement-based product. The analysis will generally be more detailed and precise than a statement of significance, which by its nature tends to be more general in scope. The whole building may have significance, but different
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RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
Significance and sensitivity (continued ) parts of its fabric will have different levels of sensitivity, which need to be identified to allow the design team to minimise potential harm. It is important when working with buildings to understand the difference between the two concepts (though perhaps less so for monuments etc.) so beware of advice notes and methodologies which do not make a distinction between the two. In general, while statements of significance are written, sensitivity analyses are best expressed graphically as marked up plans/ sections and elevations. This allows direct visual comparisons to be made between proposal drawings and the sensitivity analysis, which is a powerful tool. As the construction industry adopts a more widespread use of BIM, it is likely that the (tangible) sensitivity analysis will be the information that can be most easily embedded in the BIM model rather than the (intangible) statement of significance.
Is a building which is undesignated likely to be listed? Given the constraints that the listing of a building will impose, this will be an important question for a site of any complexity or size where there are unlisted buildings. As a very general guide, most unlisted buildings pre-1850 are quite likely to be eligible for listing and most buildings post-1919 are unlikely to be listed, but there have been exceptions within both ranges. It is now possible to get a Certificate of Immunity from Listing, usually valid for five years, which is particularly useful if there is any chance of opponents of a scheme using a request for the spot listing of a building to delay a planning/listed building application. For the design team, the primary tool for identifying and managing these issues is a heritage statement or conservation plan, which will often form the baseline for an environmental impact statement, if one is required.
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STAGE 0: STRATEGIC DEFINITION
Building ‘at risk’ An historic building which is empty or unused is generally accepted as being ‘at risk’. For some designated (listed) buildings, simply being empty is enough to place them on the ‘at risk’ register. The most commonly consulted ‘at risk’ register is compiled by Historic England and tends to concentrate on publicly owned buildings, but some local planning authorities also keep similar lists. Historic buildings which are empty and unused tend to decay much more rapidly than those that are in use. Defects such as leaking gutters or water pipes may not be spotted quickly, the building will be more vulnerable to vandalism and trespass and even the fact that doors are not being opened and closed, which reduces air movement and ventilation, can have an adverse impact.
How will the heritage assets affect the project? This question can only be answered properly once the assets have been identified and their importance established. A Scheduled Monument or a Grade I listed building will have a far greater impact on what can and what can’t be done on a project than a locally listed building or undesignated asset, and the physical extent of their influence is likely to be greater too.
Visiting a building – a guide to Risk Assessment It is very difficult to give an opinion on conservation and heritage issues without visiting the building and its surroundings. This is usually straightforward if the building is in use, but great care must be exercised when visiting an unoccupied building, particularly if it has been empty for any length of time. A prudent Risk Assessment would include: – asking the owner or checking for any relevant health and safety information, for example checking the asbestos register before going to site
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RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
Visiting a building – a guide to Risk Assessment (continued ) – telling your office when you expect to arrive at the site and when you expect to leave – letting the office know when you do leave the site – making sure that they will take action if you do not call them, carrying a mobile phone, torch etc. – wearing suitable clothes – where possible, always visiting as a pair. Falling through floors and roofs of dilapidated buildings is not unknown and you should only walk where you know it is safe. Take photographs of anything you believe may be unsafe and record the information on the plan. It is always wise to have an exit strategy.
Identify opportunities for sustaining and enhancing heritage assets These should be presented as a positive outcome of the project. There is a widespread misunderstanding that the aim of conservation is simply to preserve the historic fabric of a building. ‘Preserve’, in the sense of ‘cause no harm to’, is part of the conservation approach, particularly during maintenance in the In Use period of a building’s life cycle (Stage 7). However, it is not the key objective, simply one of a number of means to an end. The main objective is to sustain and enhance the building, in the broadest possible sense, which means maintaining historic fabric, environmental sustainability and financial sustainability. The word ‘enhance’ has broader connotations and is less well defined as an concept, but includes the removal of negative impacts (providing an easy win) and uplift through good design, both practically and aesthetically. For instance, improving public access to and understanding of heritage assets can be a powerful enhancement. There is much more benefit in conserving historic buildings if the public has better access to them and if people are provided with an explanation and interpretation of their cultural significance when they do visit. It is
30
STAGE 0: STRATEGIC DEFINITION
Can a listed building be demolished? The short answer is yes, but the current legislation sets many tests that have to be satisfied before permission will be given for partial or full demolition. Currently, the only effective argument in support of partial or total demolition is that it will deliver a greater and widely recognised public good, such as the construction of a major infrastructure project which has no other possible location. The National Planning Policy Framework (NPPF) describes the demolition of a designated asset as ‘substantial harm’ and there is a presumption against allowing this. If your scheme may propose partial or total demolition of a listed building, allow plenty of time for preparing the argument and discussing and agreeing the proposals.
better to include such ideas at the Strategic Definition stage of the project rather than as a last minute bolt-on, particularly if funds are limited.
What procurement activities are required at Stage 0? At Stage 0, the procurement activities include initial considerations for assembling the project team. Significant heritage assets will require input from consultants and contractors experienced in working on similar sites, which may limit procurement options; in particular, design and build routes are less likely to be successful because of their transfer of control over detail and execution.
What programme activities are required at Stage 0? At Stage 0, the Project Programme needs to be established. If there are heritage assets on the site, or even near the site, the overall programme is likely to be extended in comparison to projects and sites without heritage assets, in all RIBA Plan of Work stages. For example, when the Police College at Bramshill, Hampshire was sold and a new use was being proposed, Historic England requested a minimum of a year before any listed building consent application was submitted to allow access to the site and building for expert research and evaluation.
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RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
Considering town planning and listed building consents at Stage 0 At Stage 0 there may be merit in making initial contact with the local planning authority and with Historic England if the scheme involves scheduled monuments or buildings, gardens or landscapes listed at Grade I or II*. It is unlikely that there will be enough information available at this stage for formal pre-application discussions about the scheme, but it may be important as part of the Business Case risk management to get the local planning authority to confirm your assessment of which buildings are designated, the extent of the impact of that designation and possibly whether or not there are undesignated assets which have the potential to be designated. If the scheme is a large one, both the local authority and Historic England may wish to assemble their own team in the run-up to planning and listed building consent applications, and will appreciate as much notice as possible. Proposed works to designated heritage assets, such as listed buildings, will require specific consents. These can range from scheduled ancient
Beneficial use A beneficial use of a historic building is one which will, directly or indirectly: – generate an income stream to sustain the building’s operation and proper upkeep – keep it in good order for the foreseeable future (enabling it to be handed on to the next generation, for a 25–30-year period or over one major renovation cycle) – maintain the building’s cultural significance. An optimum beneficial use is one that will do this with the least possible damage to the building and, preferably, is close to the building’s original designed use. The 2012 NPPF supports this concept, although using different terms.
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STAGE 0: STRATEGIC DEFINITION
monument consent through listed building consent to conservation area consent. These are usually dealt with through the planning system; however, there are exceptions, notably ecclesiastical exemptions. Checks should be made at this stage to establish which consents are likely to be needed. This is especially important with buildings that are listed and which also have elements that are scheduled ancient monuments. In these cases, multiple processes and permissions may apply. Designated heritage assets within a project will probably prolong design development and the planning process, both during pre-application discussions and during the processing of applications. They also increase the likelihood of external stakeholders, such as the national amenity groups and lobbying bodies, taking an interest. In addition, design will probably have to be taken well into Stage 3 for a listed building consent application, and occasionally into Stage 4. This is particularly applicable for projects outside the mainstream planning system, such as work carried out under ecclesiastical exemption. The detailed discussion and negotiation that accompanies heritage assets can also directly affect the development of initial design solutions.
Conservation areas Conservation areas were first introduced in the late 1960s and are generally regarded as having been successful. They are an important tool in the planning authority’s heritage protection toolkit and considerable detailed advice is available, written by Historic England, as to how a conservation area should be identified and designated, and what the consequent effect of that designation will be. Generally, a conservation area will be determined by a conservation area assessment and supported by a conservation area management plan (CAMP). The first document identifies what is special about the area, what is positive (those factors considered to be positive contributors) and what is negative. The second document outlines how the special character of the conservation area will be conserved. The CAMP should be forward looking and give clear guidance regarding any restrictions on activity or development. For nonlisted buildings, such controls only apply to the exterior and so are less stringent than the restrictions governing the treatment of
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RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
Conservation areas (continued ) a listed building. The NPPF stresses that any control is expected to be reasonable and proportionate, even if in practice this rarely seems to be the case. The fact that a site lies in a conservation area does not preclude demolition or redevelopment, but it does give the local planning authority greater control (the extent depending on how well its CAMP is written) and a general presumption that development of any size in a conservation area should be ‘local plan led’, meaning that the site has been identified as suitable for development in the local development framework or plan, which will have been discussed and tested in public by a planning inspector. In theory, conservation area assessments and CAMPs should be reviewed and updated every five years. However, this rarely happens, which means that the applicant for a scheme in a conservation area may have to do some of this work themselves to cover emerging themes, such as setting or negative impacts, which were not even considered when the first conservation area assessments were carried out in the 1970s and which can, to a limited extent, carry the effect of the conservation area designation outside the area’s delineated boundary. The majority of conservation areas are identified on local authorities’ websites, but not all publish the supporting assessments and management plans there and it may be necessary to ask the local authority conservation officer for copies. It is also possible to ask to see the paperwork leading up to a designation as a freedom of information request. Conservation area consent is normally given as part of a planning consent. If the proposals involve demolition or major development within a conservation area then, currently, Historic England is likely to be involved as well as the local planning authority.
There is a considerable body of guidance and advice to be reviewed, understood and applied when dealing with designated heritage assets. Currently, this starts with the Acts of Parliament, then the NPPF, which is in turn supported by guidance notes published by government.
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STAGE 0: STRATEGIC DEFINITION
The need for designation Designation of cultural structures started in the UK with the scheduling of ancient monuments (Ancient Monuments Protection Act 1882) and the protection that the Act gave them against an onslaught of amateur archaeology. The designation of buildings (by the process of listing) started in 1947 and the implications of listing and the controls associated with it have been developing ever since. The current legislation in force is the Planning (Listed Buildings and Conservation Areas) Act 1990, which applies to England and Wales. The systems in Scotland and Northern Ireland are similar but not exactly the same. Recent heritage guidance produced by Historic England has tended to blur the distinctions between the various grades of listing. Although this approach may have some theoretical basis, it can accentuate the bureaucratic habit of treating all levels of heritage asset as ‘untouchable’, contrary to the precepts of reasonableness and proportionality. Designation into grades provides a useful, publicly agreed marker to determine which approach and attitudes are relevant for the building in question, and the guidance notes would be more useful and more effective if they made clearer statements on how proportionality should progress from grade to grade. The architect needs to have a clear image in their own mind of the differences that are likely to be encountered in dealing with each grade of designation. It is therefore good practice for the project architect to write or manage their own heritage assessment rather than devolving the work to someone else.
BS 7913: 2013 Guide to the conservation of historic buildings probably sits alongside the guidance notes in terms of priority, and then come the Historic England advice notes. There is also a plethora of other more or less relevant publications: Heritage Lottery Fund advice notes, Society for the Protection of Ancient Buildings guidance etc. Planning appeal case studies may need to be consulted to establish how all these publications are currently being interpreted, particularly for concepts which are difficult to define, such as a building’s setting.
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RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
Use of language in Historic England advice notes, environmental impact statements and British Standards Considerable confusion is caused by the use of the same or similar wording in different sources of information, but with different nuances or sometimes even different meanings. Typical examples are confusing significance with sensitivity; using significance differently in Historic England advice and the advice for environmental impact statements; different glossaries in the NPPF and in the current BS 7913: 2013 Guide to the conservation of historic buildings, etc. (the British Standard is particularly constrained as it has to conform to European definitions which do not precisely follow our understanding of the current usage of the terms); and the unfortunate language used by UNESCO when discussing World Heritage sites. It may be worth making it clear which version or definition you are going to adopt at the beginning of any heritage statement or conservation plan, but no definitive glossary is currently provided by Historic England. However, even then the meaning of words can be changed or weighted by planning appeal decisions and court judgments, a particular instance being the definition of ‘preserve’ in case law as meaning ‘cause no harm to’ until recent decisions on what it might mean in the context of a listed building’s setting, which broadened the whole definition again. Historically, buildings have always been best described in drawings and images and, if in any doubt, it is always helpful to include an informed diagram to clarify what you are trying to explain.
Is listed building consent required? Surprisingly, this is still a very difficult question to answer and, legally, the only people who are qualified to give a definitive answer are the local planning authority and/or a court of law (everybody else, including Historic England, can only give an opinion). Remember that a local planning authority officer’s opinion is not necessarily binding on the council, which makes pre-planning application discussions less useful than they should be.
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STAGE 0: STRATEGIC DEFINITION
It is generally accepted that works which do not alter the character or appearance of a listed building do not require consent, and this is usually accepted to mean like-for-like repair and maintenance (like-forlike meaning exactly like-for-like, not similar to or even better than). Even redecorating a listed building can require consent, particularly in the case of Grade I or Grade II* buildings, and there have been instances where lifting a floorboard to examine a floor construction was deemed to need listed building consent. There is also the question of how much of a building and its site is included in the listing. The usual interpretation is that all the building fabric and everything fixed to the building (regardless of the date when it was fixed), both inside and outside, is covered by the effect of the listing, whatever its significance; that all structures attached to the building are covered; and that ‘curtilage buildings/structures’ that existed in 1948 are included, regardless of their significance. Anything that could affect the setting of a listed building may require consent, and since the setting can generally be considered to extend up to 1km away (and 5km or more for tall buildings and structures like wind turbines), and given that the definition of setting can include more than demonstrable views, it is clear that this is an enormous grey area which needs to be clarified as soon as possible if a major project is being considered. In addition to these considerations, failing to have listed building consent in place for works is a criminal offence and such consent cannot be granted retrospectively (ie even if work carried out without consent later receives consent, the original offence still exists). Worse still, the owner of the building is liable to rectify work carried out without consent even if it was done before they owned the building. This is not a question to be treated lightly and before giving an opinion the architect should check the situation very carefully. A number of measures have been introduced recently, mainly in an effort to speed up property sales, to make it easier to find out if consent is required or if works that have been carried out are lawful. Some authorities will accept an application for a certificate of lawfulness to be used for minor activity, such as opening up the fabric for intrusive surveys, and process it in as little as two weeks. If works are proposed, the only certain
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RIBA PLAN OF WORK 2013 GUIDE: CONSERVATION
method of finding out whether consent is required is to apply for listed building consent as soon as possible. It should be noted that, although the effect of listing applies to the entire building as a legal baseline for discussion, in practice a well-prepared heritage statement (or, better still, if time and funds permit, a conservation plan) will provide a statement of significance for the site and building. This would ideally include analysis of curtilage and setting, and a relative sensitivity analysis to show which parts of the building are ‘most significant’, ‘significant’, ‘less significant’ or ‘not significant’, and specifically identify any elements which are detrimental or harmful. Note also the requirement for proportionality set out in the NPPF, and that these constraints only apply to nationally listed buildings and generally only to the exteriors of locally listed buildings (subject to specific local policies which you will need to check).
What are the Suggested Key Support Tasks at this stage? The Suggested Key Support Task for the Plan of Work at Stage 0 is to review Feedback from previous projects. From the conservation perspective this will mean identifying similar recent projects and buildings for comparison, for use as reference points in later discussions. At this stage you need to: I achieve an initial consensus on the general statement of significance for the site and buildings – this will inform programme and procurement issues I remind all concerned that causing harm to a listed building can be a criminal offence. For some people and organisations even the threat of criminal proceedings can have significant repercussions, and eliminating any possibility of such a threat can be time consuming, which may need to be recognised in the Strategic Brief and the Business Case.
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STAGE 0: STRATEGIC DEFINITION
What are the Information Exchanges at Stage 0? Information Exchanges required for Stage 0 are as follows: I at stage completion: the Strategic Brief I UK Government Information Exchange is not required. Although the Strategic Brief is the only Information Exchange at this stage, it will be more robust if it includes a plan of the area around the site/building, identifying known heritage assets and providing a short summary of the likely effect of those assets on the scheme in hand.
Working on buildings in use: an appropriate mindset The heritage assets that architects are generally involved with are buildings in use. They are tools with a function to fulfil – as opposed to monuments, archaeological finds and museum pieces which no longer have a function or use and are kept purely for their own sake. The distinction is important as the conservation of a building in use is fundamentally different to the conservation of monuments, archaeological finds, museum pieces etc. in that periodic change will be necessary to keep the building functional and in use, in addition to ongoing repair and maintenance. The conservation of monuments, archaeology and museum pieces rightly focuses on the ‘preservation’ end of the conservation activity spectrum. Many of the people who work to implement heritage protection legislation and who write the advice notes that inform that work come from archaeological or art historical backgrounds. This promotes a ‘need-to-preserve’ mindset at the expense of a broader, proactive forward-looking approach based on practical experience, which is the essence of effective long-term building conservation. However, the fundamental mindset required when working with historic buildings is one of respect.
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Chapter summary
0
This chapter has looked at the input that may be required from a conservation viewpoint in defining the strategy for a project. The principal activity is to identify the existence of heritage assets on or around the sites under consideration and gain an overview of their quality or significance. In the case of buildings or built sites it is also important to identify whether the assets are at a point of challenge or major change, to outline opportunities for sustaining and enhancing the heritage elements and determine whether or not any harm that may arise from the proposals can be balanced by a greater public good. For buildings, a key concept is that of beneficial use. The approach taken to a building in use, which is a functional tool, will be different to that adopted when dealing with a museum artefact, an archaeological find or other heritage assets which no longer have a function. This input will inform the Strategic Definition of the project, in particular regarding cost allocation, programme and the risk register.
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Stage 1
Preparation and Brief
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Chapter overview Having established that there are historic buildings and/or other designated heritage assets on or near the site, the design team should now be gathering information about the site and buildings to start to differentiate the relative values of the various elements found. Even with a Grade I listed building it is unlikely that all parts are equally valuable and the general aim is to direct the brief towards intervention in the less valuable parts. This approach is consistent with the concept of proportionality built into current heritage protection legislation. The key coverage in this chapter is as follows: Identifying external heritage receptors Drafting a statement of significance Identifying surveys and research needed Advising on the procurement route Measured survey of the existing buildings and site
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Introduction The main task at this stage is to draft a statement of significance for all heritage assets that may be affected by the project. The statement of significance will be the conclusion of a report called a heritage statement (or, if sufficient time and resources are available, a draft conservation plan). This report is an increasingly important precursor to pre-planning application discussions and is expected to guide and inform the client’s brief and the design team in their early thinking. Producing the draft will highlight areas that need further investigation or research. It may also inform the choice of procurement route. This is also the time to obtain a high-quality measured survey which is useful for building analysis as well as providing a good foundation for design development.
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What are the Core Objectives of this stage? The Core Objectives of the RIBA Plan of Work 2013 at Stage 1 are:
1
Tasks Tasks
Core Objectives
Preparation and Brief Develop Project Objectives, including Quality Objectives and Project Outcomes, Sustainability Aspirations, Project Budget, other parameters or constraints and develop Initial Project Brief. Undertake Feasibility Studies and review of Site Information.
The initial task at this stage is to identify external heritage receptors. The quickest way to do this is to conduct a site-centred map search on the Historic England website, Heritage Gateway (Figure1.1). By manipulating the layers you can show the locations of all listed buildings and other designated assets and links to their listing descriptions.
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Figure 1.1 Screen shot of the Heritage Gateway website. © Historic England. © Crown Copyright and database right 2017. All rights reserved. Ordnance Survey Licence number 100024900
How to draft a statement of significance Begin by collecting information about the site and buildings that is readily available. Preparation for this includes a site visit, initial visual assessment and general photography and a review of published information. The information gathered by these methods is used to build up an understanding of the place (sometimes called ‘the spirit of the place’) and an analysis of its cultural significance under the following headings: I historic value I aesthetic and architectural quality I technical innovation
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I community value I evidential value (essentially the quality and extent of documentary and other external references to the site and building). The summary of your findings is then presented as a heritage statement with a ‘golden thread’ leading through the understanding of the place to the draft statement of significance, written using the terms and vocabulary found in the NPPF glossary. The statement of significance will inform Project Objectives and Quality Objectives and will guide the Project Outcomes. The heritage statement will become part of the Initial Project Brief and is used to define the envelope of possibility for the site and to inform the Feasibility Studies, usually in an iterative manner.
Assembling the design team If at all possible, make sure that the other members of the design team have relevant experience of working with historic buildings and within the limitations of listed building consent. Experienced structural engineers tend to be much less demanding of an existing structure than those who base their analysis and advice on modern standards. Experienced building services engineers will be able to think outside the box at an early stage and envisage novel solutions rather than simply demanding unfeasibly large zones for ductwork and plant etc. Look to the accreditation schemes now operated by the various professions and to conservation directories for leads to appropriately experienced people but, above all, personal recommendation and experience.
Checking administrative boundaries While most projects that an architect is involved in will lie within a single administrative area and there will only be one local planning authority to deal with, it is not unheard of for a large building to cross the administrative boundary and so be subject to control by two separate local planning authorities. Usually, in such situations common sense will prevail, but this is not always the case. If this is the situation you are confronted with, it is
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Checking administrative boundaries (continued ) important initially to warn your client of the potential for delay and confusion and then to make every effort to establish an agreed way of working with both authorities. You will probably still have to make multiple applications for planning and listed building consent, which may of course run on different time schedules. Careful and thorough public consultation is essential in such circumstances. Similarly, large urban sites may lie within more than one conservation area, which may have slightly different assessment policies and management plans. You should be able to establish administrative boundaries by checking the local authorities’ websites. Be aware that the Planning Portal may not highlight this issue.
World Heritage sites World Heritage sites are areas or landmarks officially recognised by a system of designation operated by UNESCO as significant to the collective interests of humanity. There are no specific planning or other requirements which relate to them, but any proposal which affects a World Heritage site or its setting will come under particular scrutiny. This can also be true of sites which have been proposed for World Heritage status but which have not yet been accepted as such. The NPPF guidance notes are the primary source of advice on World Heritage sites.
Identifying surveys and research needed The draft heritage statement will review current site information and will include recommendations for further research and investigations. It is important to give advice on the need for specialist input, and the likely range of investigations and surveys that will be necessary, as these can all affect the Project Budget. Regardless of the complexity of the site, input will be needed from a number of disciplines. It is usually
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Dating elements of building fabric This is a skill acquired by experience, and many mistakes are made! Key developments, such as the earliest use of sash windows or the widespread introduction of mild steel, can provide ‘not earlier than’ dates, as can dating by style and detailing. However, it could take many years for the use of a particular style or detail to ripple outwards from London, or wherever it was first adopted, into other parts of the country, and copying of earlier styles is not uncommon. Remember that some objects, such as panelling, floorboards, fireplaces, doors and windows have often been moved within a building and occasionally between buildings. Practice makes perfect, so always hazard a guess, but remember it is a guess.
more effective to bring in other disciplines at this stage, at least for an initial review, rather than later on. Input may come both from professionals and from supply chain members and craftspeople, especially in cases where there is likely to be a degree of specialist repair or restoration involved. Don’t forget to advise whether primary research work relating to the buildings and site is necessary and any likely locations of relevant material, as well as who would be best placed to undertake the research. This advice will usually follow from the initial statement of significance and sensitivity analysis. By its nature, the time needed for this research is hard to predict and the work may not necessarily come up with a clear or positive result. In any case, the extent and objective of any research should be very clearly defined. Another task which may be useful at this stage is a review of the retention of the embedded energy in any existing buildings; doing this should reinforce sustainability objectives. Energy-in-use calculations and predictions are notoriously unreliable at present, and should therefore always be kept in balance with estimates of embedded energy. It should be noted that assumptions made about the performance of modern building materials (such as U values) are not necessarily directly applicable to historic building fabric and it may be necessary to initiate site testing and occasionally commission research work to establish the likely performance
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Sustainability and embodied energy The goals behind the conservation of buildings and design to reduce energy use and carbon footprint are at least parallel, if not convergent. There is a truism which says that a building which has stood and been used for 100 years has proved its worth and adaptability, and so should be able to continue working for the next 100 years. The energy embodied in such a building is precious and should not be wasted by unnecessary change or demolition, and should certainly be included in any sensible calculation of energy/carbon balance. A study by the Ministry of Justice in 2007 concluded that its modern building stock only started to match the environmental performance of its nineteenth-century stock in the late 1990s and early 2000s. Do not assume that existing buildings underperform.
of historic construction. In practice, historic buildings have been shown to perform far better in terms of energy use than modern calculation methods tend to predict. It is worth reiterating, to make sure that the client and their advisers fully understand, that carrying out works without having listed building consent in place is a criminal offence. Moreover, even if no formal action is taken, there may be serious consequences for the reputations of all involved.
Measured survey It is also important that you advise the client on the time needed to specify, tender and undertake preliminary survey work, such as measured surveys and non-intrusive investigations. A proper measured survey is a key tool in analysing and understanding a historic building of any complexity, but measured surveys that consist only of plans for room area calculations and the like are rarely sufficient. Architects should take control of the specification of measured surveys to make sure that they get the information they need, and state the levels of accuracy and detail required. Measured surveys should always be undertaken in a way that allows the accurate integration of later measurement, in particular following discoveries on site and during opening up. They need to be coordinated and checked in the vertical as well as on the X and Y axes.
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Energy performance and U value calculation There is increasing evidence that the calculations used for assessing U values, and hence predicting heat loss, are not particularly accurate and more especially so for older buildings pre-1919 (roughly when cavity walls came into widespread use). More research is assuredly needed but, in some cases, traditional solid masonry walls have been shown to perform almost 33% better than the calculations indicate, while some modern constructions were found to perform worse than predicted. This is an important factor to consider when assessing energy use and plant sizes (there is very rarely enough room in a historic building for the generous space allocation of a modern plant room). Fitting modern services into historic fabric without causing undue damage is difficult at the best of times, so keeping the size of distribution pipework and its insulation to a minimum is necessary and a range of heating strategies may be needed. For some types of use the strategy will be to heat the people not the building, so approach these issues with an open mind. It is also important to have accurate information when deciding whether or not energy performance requirements are best achieved by demolition and rebuilding rather than careful renovation. Taking site measurements of heat transfer through the existing fabric may be the best way of getting an accurate picture of these issues, but it will need to be a large project to justify the expense and there are not many people with the knowledge and experience to carry out these investigations and they tend to come from the research community rather than the commercial sector. There are similar concerns about the general accuracy of interstitial condensation calculations, particularly in terms of their accuracy and relevance when dealing with heavyweight historic construction. Any calculation of this type needs to be treated with caution. The advantage of an existing building is that you can observe what has been happening and measure performance directly if sufficient time and resources are available.
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Building Information Modelling (BIM) If the project is to be run using BIM techniques, this will require particular methods of measured survey of the building in order to be effective. This approach can have potentially significant time and cost implications, depending on the complexity of the building concerned. A key issue in building the virtual model will be whether or not voids can be accurately identified, and who will describe the build-up of the building’s existing construction within the model, and how to apportion liability for doing so. It is highly likely that the file size of the measured survey model will be much greater than would be expected for a new build, even before the start of design work. This means that many components will have to be described generically or assembled individually.
Modern techniques such as 3D cloud laser scans are ideal for conducting measured surveys, but can create very large file sizes. All measurement techniques rely on a degree of interpretation by the surveyor and it is often worthwhile to have a sample area surveyed and drawn up in detail to agree standards and presentation before undertaking the full survey. Clearly, though, this can take time. You should also check that the specifications for such work are adequate for the significance and complexity of the building and other assets concerned. The statement of significance and initial sensitivity analysis should help to identify the most productive areas for non-intrusive investigation, typically at junctions between constructions of differing dates, but this will be an ongoing process. Cloud laser scan This is also known as a point cloud survey. It is obtained by setting up a rapidly firing laser head at a known reference point and then recording the millions of reflections of the laser beam back from the building. This creates the ‘point cloud’ which is the primary survey. Note that it is a line of sight survey (ie there will be shadows from any particular survey point) and that it only measures the building’s surfaces. The point cloud can then be interpreted by software to build a solid 3D model. Lines of sight and shadow issues can be overcome by having multiple survey points to provide full coverage.
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The ‘skin paint’ 3D model then needs to be interpreted again to build up the likely building construction, if that level of modelling is required. An advantage of the cloud laser scan method is that the level of detail set at the first build of the 3D model can be upgraded later at specific points if required. Software to interpret cloud laser scans is improving all the time, including programs that can ‘learn’ and identify shapes, such as a cornice moulding, and model them as components.
What procurement activities are required at Stage 1? When defining project roles, consider the appointment of accredited conservation architects within the design team. There is an increasing expectation that accredited specialist conservation architects should take a lead role in the design team when working on designated buildings at Grade II* level and above, and some funding bodies may insist on it. This is a good point to consider procurement of the construction work. Many people find that traditional construction contracts are better suited to conservation work than routes that require complete definition (such as NEC contracts) or ones that transfer risk and design responsibility to the contractor. This is because when working with historic buildings there will always be many unknowns, and sometimes surprises and discoveries, once work starts on site and the building is opened up. The construction contract should be capable of dealing with such circumstances without undue penalty to either party, or loss of control of the final outcome. In forms of procurement which transfer more risk than the traditional contract there are likely to be heavy costs associated with the problems of latent defects and lack of reliable knowledge about a building. It has been argued that responsibility for latent defects cannot be transferred. If you are in a team that is being asked to take on such a responsibility, check your professional indemnity insurance carefully!
What programme activities are required at Stage 1? A conservation plan may have a number of contributors from different disciplines and theoretically should be a consultative document, broadly
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agreed with stakeholders such as the local planning authority and Historic England. Sufficient time must be allowed for interested parties to read, absorb and comment on the plan. If this is not done, the plan will have much less credibility when it is submitted to funding bodies or as part of a planning/listed building consent application. This is why teams often produce a heritage statement rather than a full conservation plan at this stage. Ideally, a conservation management plan will be substantially drafted and discussed before design development work starts in earnest. Intrusive surveys may need listed building consent, which will take two to three months for an application to be processed. At the least there should be written agreement with the local planning authority as to what can be done without consent.
Considering town planning and listed building consent at Stage 1 The heritage assessment is a useful tool for opening discussions with the local planning authority/Historic England, who will generally expect to see and discuss such work before looking at any design proposals. It can also be a useful tool for opening conversations with external stakeholders, such as national amenity societies and local interest groups. A key objective is to get early agreement and definition of the statement of significance and to establish any areas where there is a lack of consensus or where further work is needed to reach agreement. Listing descriptions, particularly modern ones, are a useful starting point but rarely have sufficient information or definition to act as a statement of significance. Originally, the listing descriptions were used to help identify the building or site being designated, in the absence of photographs or GPS reference points, and it is not unusual for there to be no description of the interiors. The fact that a feature is not mentioned in the listing description does not mean it is not listed and designation applies to the whole building, inside and out. Care must be taken regarding what are known as curtilage buildings, which may be included in the general designation, and increasingly with subjective attributes, such as the setting of the building/site and of other nearby buildings/sites and monuments which may be regarded as
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potentially affected by any proposals. For prominent and tall structures the area to be assessed may be extensive. You should advise the client if there are undesignated buildings on or near the site which may be spot listed. This can cause significant delay and requests for spot listing have been used as a means of delaying or obstructing schemes. Based on what you find, do not forget to advise whether there is a case for applying for a Certificate of Immunity from Listing. The regulations and procedures relating to applying for a Certificate of Immunity have recently changed. It is also important to check existing consents and take a view on whether any works have been carried out without consent and advise the client accordingly.
Statements, assessments and plans The documents to be produced for a conservation project can be summarised as follows: For buildings, the sequence is: 1. Heritage statement (formerly referred to as the conservation statement) 2. Statement of significance 3. Conservation plan (which may be regarded as a Project Strategy) 4. Conservation management plan (which may occasionally be developed into a heritage partnership agreement). For conservation areas, the sequence is: 1. Conservation area assessment 2. Conservation area management plan (CAMP) (which should be written by the local authority).
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List
tify Ide n
ing
heri tage ass des ets crip Und t i o erst n (id and enti ing Cul fier) the tura plac l si gnif e Roo ican mg ce ( aze in c ttee Sen onte r sitiv xt) ity a naly Vuln sis erab ility Iden tify issu es Poli cies Man age men 10 y t of ear the ma i poli nten cies Sch edu anc e pl le o an* f rep 30 y etiti ear ve m rolli ng p inor Enr ichi rog wor ng t ram ks he L me ist
STAGE 1: PREPARATION AND BRIEF
Strategic review Heritage statement Statement of significance Conservation plan Conservation management plan Management and maintenance plan Heritage protection agreement 4-yearly/5-yearly inspections * HLF requirement
Figure 1.2 Sequence of documents throughout a conservation project
What are the Suggested Key Support Tasks at this stage? I Prepare a draft Handover Strategy and Risk Assessments. These will vary depending on whether a full conservation management plan is instructed. I Identify opportunities for the enhancement of the heritage assets, such as the importance of delivering good design, which can also include removal of negative impacts. I Review opportunities for the inclusion of explanation and interpretation of the heritage assets identified in the heritage statement.
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I Establish a strategy for improving inclusive public access to key elements or key areas identified in the statement of significance. SWOT (Strengths Weaknesses Opportunities Threats) analysis and risk analysis can be useful means of doing this and of identifying what is often termed ‘the least bad solution’. I Health and safety risk analysis should include an assessment of any materials that may be present in the existing construction, such as lead-based paint, which require special measures for their management and reuse. I The removal of asbestos can have a major impact on the Project Programme and budget as well as on the historic fabric, with the added issue of managing the work of removal when it has to be carried out behind screens and without ready access for inspection until the work is complete. I Health and safety plans for visiting sites and buildings where structural integrity is uncertain need early and careful consideration, and should be updated as the project progresses. This is also a good stage to start reviewing the security of the building and its contents, particularly if it is or will become empty. Some valuable elements, such as fire surrounds, may warrant immediate protection, but make sure that they have been photographed and recorded before this happens. Some local authorities will require a salvage and protection plan as part of a listed building consent application.
Sustainability As mentioned above, it may be useful at this stage to review the embedded energy in any existing buildings; doing this should reinforce sustainability objectives. The philosophies of heritage conservation and long-term sustainability are very similar in this respect, because they both believe in minimising the loss of existing fabric as a fundamental principle.
What are the Information Exchanges at Stage 1? Information Exchanges required for Stage 1 are as follows: I at stage completion: the Initial Project Brief I UK Government Information Exchange is required.
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Chapter summary
1
Having established that there are historic buildings and/or other designated heritage assets on or near the site, the design team should now be gathering information about the site and buildings to start to differentiate the relative value of the various elements found. This is presented as a draft statement of significance for all heritage assets which may be affected by the project. The statement of significance will be the conclusion of the analysis contained in the heritage statement (sometimes called a conservation statement). This report is an increasingly important precursor to pre-planning application discussions and is expected to guide and inform the client’s Initial Project Brief and the design team in their early thinking. If a high-quality measured survey is not available already, this is a good time to commission such a survey, particularly if there is a requirement to use BIM.
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Stage 2
Concept Design
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Chapter overview At this stage of the design, work options are tested to establish the likely extent and location of interventions, removals from and additions to the building. These studies will be informed by the developing conservation plan or heritage statement and will form the core of discussions with stakeholders. They will be the basis of the design and access statement and preparation for the submission of applications for planning and listed building consent. The key coverage in this chapter is as follows: Development of the heritage statement Draft impact assessments Surveys and research Specialist input Development of a BIM model
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Introduction This chapter looks at the development of the heritage statement into a conservation plan and at establishing an ‘envelope of possibility’ in conservation and heritage terms which will inform the direction of the Concept Design, often in an iterative manner. This work is tested through option studies and discussion with the client, within the design team and with external stakeholders. The team should be looking not only to sustain the site/building but also to seek to enhance it where reasonably possible. Enhancement can be used to balance or mitigate any damage caused by intervention.
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What are the Core Objectives of this stage? The Core Objectives of the RIBA Plan of Work 2013 at Stage 2 are:
2
Tasks Tasks
Core Objectives
Concept Design Prepare Concept Design, including outline proposals for structural design, building services systems, outline specifications and preliminary Cost Information, along with relevant Project Strategies in accordance with Design Programme. Agree alterations to brief and issue Final Project Brief.
Develop the heritage statement into a conservation plan Work to inform and support the developing conservation plan (which should be treated as a Project Strategy) will include: I filling any gaps identified in the existing information set I map regression to show site history I archaeological desktop study (by a CiFA member with appropriate experience) I working up the measured survey, particularly layered structures, room numbering etc. to make it useful for analysis and as a design tool I undertaking a catalogue search of local and national records and procuring copies of published historic drawings and photographs
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I producing a photogazetteer of the site, building and interiors, both as a record and as an aid to off-site discussions (depending on the technique used this may form part of the measured survey) I if a BIM model is being used, linking the gazetteer to the model I specifying, procuring and managing non-intrusive surveys and investigations, such as paint analysis I undertaking a condition survey of the fabric, if not already done I assessing undesignated heritage assets, including those with a negative impact I identifying issues relating to the site and to the fabric of the building (such as poor provision of inclusive access, fabric elements reaching the end of their life cycle, lack of interpretation and explanation of the history and value of the building) I developing general policies for the long-term conservation of the building. The conservation plan can then be developed into a conservation management plan, which will include a section for each issue that details: how that issue will be dealt with, which policies will affect it, who should deal with it, and what the time frame will be. The conservation management plan can also include a section on maintenance, giving guidance on how to deal with routine matters, which in turn can be linked to the operation and maintenance manuals that will be produced at the end of any major programme of work. Input may come both from professionals and from supply chain members and craftspeople, especially in cases where there is likely to be a degree of specialist repair or restoration involved. This work will lead to a drawn analysis of: I the development and morphology of the site and buildings I definition of views, setting and curtilage I first pass dating of the historic fabric, preferably in plan (and section) form to allow direct comparison with proposals I sensitivity, concentrating on spaces, fittings and finishes I any site-specific furniture or collections. Being drawn, in plan at least and, where possible, elevation and section, the analysis can be directly compared with emerging options and Feasibility Studies and will inform risk analysis.
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For most projects, these studies will then be assembled to form a draft conservation plan, which at this stage may conclude with a masterplan. The format of a conservation plan will generally adopt the following structure: 1. Understanding the place what are we dealing with What is the history of the site, buildings and people associated with it? 2. Statement of significance What is important? Who values it and why? (These first two sections are sometimes described as identifying the spirit of the place.) 3. Issues and vulnerability What is wrong and what could be better? 4. Policies Proposals for dealing with issues and vulnerability over time. Understanding the place essentially provides a history of the site and buildings, together with the events and the people associated with it, and any site-specific architectural or technical interest, showing clearly why the buildings/site are of cultural value and, where possible, identifying who it is that values them. Often the design team will need to have input from specialists for this element of the conservation plan, particularly for a large and complex building. Specialists who could be required to provide input include: architectural historians, especially for identifying similar buildings and providing comparisons; people with detailed knowledge of particular building components, such as fireplaces, doors, windows or moulding details; and people with specialist knowledge of the history and dating of construction techniques. The ICOMOS principles stress the need to bring together the best knowledge available, and a conservation plan is often a collaborative effort. Photogazetteer Some people place a gazetteer here as part of the main structure of the conservation plan. This can be a large body of work whose sheer bulk can impede the flow of the conservation plan, which should ideally be a concise and easy read. The gazetteer is usually better placed as an appendix. Not all conservation plans will need a photogazetteer but it is
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a useful record and a useful working tool, particularly for large buildings or buildings with restricted access. They can be time consuming to prepare so check whether a gazetteer is needed when pricing this work. Statement of significance This should be succinct and as precise as possible, covering architectural and aesthetic value, historical value, social or community value and scientific or technical value. In some cases, spiritual value will also be included. These categories roughly correspond to the cultural values considered when a building is being assessed for listing. The cultural values are largely intangible, and often subjective, particularly in terms of judging their weight and importance, and are subject to change in opinion and knowledge. Cultural values can change over time, sometimes quite quickly. Sensitivity and vulnerability analysis To inform design work, tangible output, such as the dating and sensitivity analysis, needs to be developed in drawn format and supported by vulnerability analysis, usually based on a recent condition survey. Some buildings will also need room-by-room analysis, particularly where notable features are present, such as fine fireplaces, decorative plasterwork, original equipment or similar items. This work analyses the historic fabric, the physical aspect of the building as it currently stands, and starts to define the ‘envelope of possibility’ of what can be done where in the building, as well as what needs to be done. Policies for the management of change in the building and its site should be developed, which should show how the significance of the site and buildings will be sustained and, where possible, enhanced. Policies can range from guidance on maintenance and repair to the future of the site and building in the medium to long term, concentrating particularly on sustaining beneficial use, which, broadly defined, is a use (preferably the original design use) which will generate sufficient income to finance the long-term maintenance, repair and, occasionally, development of the heritage asset. These principles should recognise the life cycles of the building fabric and the frequency with which the type of building may be challenged by changes in legal, technical, operational and aspirational requirements.
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Masterplan In addition, particularly for larger sites, the results of the studies may be expressed as a drawn masterplan, which, as with the sensitivity analysis, allows direct comparison with option studies and emerging proposals. Otherwise, a statement of opportunities (and threats) may be sufficient. This work will feed into the Cost Information and option studies, and will directly inform the Project Strategies, particularly if the conservation plan is to be developed further into a conservation management plan. The conservation principles and associated forward-looking plan should be integrated into the developing Initial Project Brief. A conservation plan may be further developed into a conservation management plan, which will develop the principles established for the site into a forward-looking set of actions, ideally allocated to particular people or bodies (client, contractor, professional advisers, local planning authority etc.) and with indicative timescales. If the conservation plan is extended in this way, the work will probably cross Stages 2 and 3 and will be updated in Stages 5, 6 and, eventually, 7. The conservation plan is also very useful for developing initial strategies for MEP plant locations and primary distribution, based on the sensitivity analysis. The impact of these strategies should be tested with the structural engineer.
Draft impact assessments As the scheme develops, the heritage statement/conservation plan provides a baseline for heritage impact analysis. Bearing in mind the need to be proportionate, discuss with the team (and the local planning authority) what level of detail is required. Heavily detailed tabular assessments are often less useful than an informed general assessment.
Surveys and research Stage 2 is, for many, the right time to instruct surveys and further research identified and scoped in Stage 1, to inform both the Concept Design and the heritage analysis.
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Primary sources for research – The local historic environment record (HER) (NPPF states that this is the minimum required). – Heritage Gateway: Historic England’s website, which is much more accessible than most HERs. – The listing description, available from the Heritage Gateway. – Pevsner Architectural Guides. – Victoria County Histories. – Survey of London. – H.M. Colvin’s biographies of architects. – Local records office. – Map regression. – Public Records Office at Kew. – National Monuments Record at Swindon. – RIBA collection and library. – Historic aerial photography. – Wikipedia (treat this source with caution – it should only ever be a starting point). An experienced researcher will very quickly get an idea of where else to look and a feel for what there is to find out. Ongoing improvements in online catalogues are helping to make primary searches less time consuming and more effective.
Intrusive surveys (opening up) can be scoped at the end of this stage, but may need listed building consent so are often not carried out until later. Developing the BIM model Although BIM is about much more than the use of 3D modelling software, for design teams this is currently the primary consideration when dealing with a request to work in a BIM environment. There is a great – but at present unfulfilled – opportunity to integrate conservation analysis with a BIM model, and some architects have shown how effective this can be. However, developing a full BIM model from a simple surface model (usually based on a cloud laser scan) can be time consuming. It may also carry unrecognised liability, unless it can be made very clear which parts of the model are based on direct measurement and survey and which are extrapolation and interpretation.
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In addition, for reasons of speed and efficiency, commonly used 3D modelling software often relies on the use of standard models of building components, such as windows and doors. These are provided by manufacturers or are available from general component libraries. In historic buildings, elements are often not consistent: they might be highly decorated, or are in reality damaged or distorted. Modelling the individual components can therefore be as time consuming as modelling the building itself. A simple 3D model will be very useful for visualisation and coordination with other disciplines, but a complex, fully detailed model may become too large and unwieldy to be useful to the design team, the construction team or the future users of the building. If it has not been done already, this is the stage when the levels of detail and information expected in the BIM model are finalised and agreed. There should be a very clear statement of which elements of the design will be managed in a 3D model and which will be developed using more traditional methods. The balance will shift as computer software and hardware develops, and especially when clients use BIM models operationally.
What procurement activities are required at Stage 2? As the scope and extent of works to the historic fabric becomes clearer during this stage it will become easier to decide on the best procurement route for construction work in general. In many cases, the traditional construction procurement route will be most appropriate, although developer-/contractorled design and build has, on occasion, been successful if the Initial Project Brief and Employer’s Requirements have been sufficiently well defined. However, if this is the chosen procurement route, it is usual to tender only after receiving listed building and planning consents. Forms of contract such as ‘cost plans’ and ‘construction management’ may be suitable for work on existing buildings even if they are usually discounted for new build work. This is also a good stage to engage with specialist craftspeople and suppliers, to establish their capabilities, capacity and lead-in times.
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What programme activities are required at Stage 2? Impact on the Project Programme at this stage depends very much on the amount of information already available and its quality, together with the complexity of the site and buildings, and the degree of change and intervention anticipated. If it has not already been done, a gap analysis of existing information can be very helpful, as can conversations with people who use and manage the building, if it is in use. Checklists are a useful tool for this task. The overall Project Programme can then be updated to show the timing for the specification, procurement, site work and reporting of non-intrusive investigations, intrusive surveys (check whether they need listed building or other forms of consent), more wide-ranging pre-application discussions and consultations, the potential for an extended design period before submitting planning and listed building applications, and possibly an extended period for the determination of applications.
Considering town planning and listed building consent at Stage 2 The conservation plan/heritage statement will be a key part of any application for planning and listed building consent. It should underpin the design and access statement (currently a requirement for listed building applications) and the design proposals submitted should clearly derive from it. It will form the basis for the heritage impact assessment, which will usually be part of the design and access statement, but on larger or more complicated projects will be a separate report. If the project is large enough to require an environmental impact analysis, the conservation plan will form the baseline report for the heritage section of the environmental impact statement that will be submitted as part of the planning application. Intrusive surveys may be required. Care should be taken to agree with the local planning authority, before the surveys are undertaken, whether or not they need listed building consent. Decisions in this area can be very subjective.
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If the proposals are relatively simple and uncontroversial it should be acceptable to submit planning and listed building applications at this stage of work, but many local authorities expect a design to be submitted during Stage 3. A listed building consent is a very specific form of approval. If works are not shown on the approved drawings then they do not have consent – work cannot be inferred. Occasionally it has been deemed necessary to obtain Building Regulations approval before a consent is granted, but this should not usually be necessary. For the majority of schemes, an application for listed building consent and planning will be made in Stage 3. It is increasingly common for local planning authorities to have no inhouse conservation expertise. If a site, building or project warrants it, an external adviser may be appointed to monitor and comment on proposals. Ideally, this process forms part of the pre-application discussions. If there is a formal pre-planning agreement, an important part of it will be to agree a suitable person or organisation to fulfil this role. If listed buildings are involved, it should be someone formally accredited in the conservation of buildings under a recognised scheme (see the Historic England advice) and with relevant practical experience of the type of building concerned.
Pre-application discussions In theory, these are a good idea. However, since both local authorities’ planning departments and Historic England will, in principle, charge for ‘pre-apps’ and may or may not feel bound by any advice they give – even if they do give it in writing – their actual usefulness has to be considered carefully. It may be quicker and cheaper to submit a listed building application, because even if it is refused you will get a full written statement of the reasons for its refusal. There is also the inevitable human factor that when preapplication discussions are held the available information is often incomplete and the local planning authority officers will tend to err on the side of caution. They may also subjectively come to a fixed position from which they are hard to shift regardless of the information subsequently presented to them. Prepare carefully before engaging in pre-app discussions, and be very clear about the answers you are seeking.
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What are the Suggested Key Support Tasks at this stage? I I I I I
Prepare the Sustainability Strategy. Prepare the Maintenance and Operational Strategy. Review the Handover Strategy. Review the Risk Assessments. Undertake third party consultations as required and any Research and Development aspects.
A conservation management plan will contain sufficient information and detail to inform Maintenance and Operational Strategies. It can also be developed at a later date into a heritage protection agreement if the facilities managers and local planning authority agree that this is a useful course of action. A heritage protection agreement allows a defined range of relatively minor and routine tasks to be carried out by building owners without having to apply for listed building consent every time. There is likely to be a growing integration between conservation management plans and BIM models. However, this is new territory and the means for achieving this integration are not certain. The conservation management plan will incorporate third party consultations on heritage issues and identify areas of future research. I Review and update the Project Execution Plan. The heritage input for this activity will relate to risk review and the predicted programme for the future stages. I Consider the Construction Strategy and develop the Health and Safety Strategy. This will include an early draft of a salvage and protection plan and lists of likely specialist sub-contractors or suppliers. The Health and Safety Strategy will start to identify any potential clashes between modern good practice and the need to conserve historic building fabric; typical issues include the adequacy of guarding on historic balconies and staircases and provision of safe access to routes for rooftop inspections and maintenance.
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Sustainability Strategy Environmental calculations that are deemed reliable for modern construction may not be appropriate for historic building fabric. Historic buildings are often heavyweight compressive structures, which rely on absorbing and then releasing water vapour rather than having barriers to vapour passage. Great care is needed in applying modern materials techniques and energy-reduction theories to historic fabric and it is preferable to undertake direct measurement of items such as U values rather than rely on published figures. If in doubt, don’t do it. Make full allowance for the energy already embedded in the building. Generally, historic fabric needs to breathe and overzealous sealing of the fabric to achieve airtightness can be extremely detrimental. This stage is a good time to carry out any non-intrusive surveys identified as necessary and possibly procured in the previous stage, such as infrared scanning and radar passes, which can identify voids, fissures and dampness within the body of historic fabric and the location of ferrous metals likely to cause problems in the future. It may be necessary to follow up with localised intrusive surveys to confirm the results.
What are the Information Exchanges at Stage 2? Information Exchanges required for Stage 2 are as follows: I at stage completion: Concept Design including outline structural and building services design I a draft heritage impact assessment I associated Project Strategies I preliminary Cost Information I Final Project Brief I UK Government Information Exchange is required.
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Chapter summary
2
This chapter has detailed the process of producing a heritage statement/conservation plan, which starts by identifying the current consensus on what cultural value a site and/or building has and determining which parts of the site and building show that value most clearly, so directing change to other parts of the building in order to minimise impact on the building’s cultural value. The thinking process is similar whether or not an actual conservation plan is produced and there are a number of reports, such as heritage statements, heritage impact assessments etc., which cover part or all of the same ground in varying levels of detail but which will be more project-specific than is expected from a conservation plan. A distinction is made between cultural significance, which is what we are seeking to sustain and pass on to future generations and which is generally intangible, being about ideas which are subject to change, and the sensitivity of the historic fabric, which is tangible and may to some extent express the cultural significance. However, simply because a piece of fabric is sensitive it does not follow that it is necessarily significant. In very broad terms, significance is a planning/listed building consent issue while sensitivity informs the technical approach to finding suitable design solutions for the building.
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Stage 3
Developed Design
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Chapter overview Many projects involving a listed building will be submitted to the local planning authority for planning and listed building consent towards the end of Stage 3. This is because listed building consent is specific to the design and detail submitted, and usually more detail is required to consider the implications of a proposal than would be the case for a new or unlisted building. More supporting documentation and explanation of alternatives considered may also be required. This stage moves conservation work from description and analysis of what exists into coordinated technical strategies which aim to minimise adverse impact on the historic fabric and maximise any opportunities for enhancement. The key coverage in this chapter is as follows: Developing the coordinated design Completing the conservation plan Preparing the design and access statement for the listed building consent application Preparing the heritage impact assessment for the listed building consent application Developing input from specialists Advising on design detail and specification Engaging with potential suppliers and craftspeople
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Introduction In this stage, conservation activity within the design team is moving from the descriptive, analytical and theoretical towards the practical strategy of technical solutions and their coordination. The design team will need a good grasp of the range of technical solutions available and their appropriateness to the job in hand. Although for some simple projects it is reasonable to apply for listed building consent at the end of Stage 2, design details in the majority of projects will not be sufficiently resolved until the end of Stage 3.
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What are the Core Objectives of this stage? The Core Objectives of the RIBA Plan of Work 2013 at Stage 3 are:
3
Tasks Tasks
Core Objectives
Developed Design Prepare Developed Design, including coordinated and updated proposals for structural design, building services systems, outline specifications, Cost Information and Project Strategies in accordance with Design Programme.
Development of a coordinated design Integration and coordination of structural works Structural engineers with experience of historic buildings will tend to offer more economic and less intrusive solutions than those who simply apply current codes. Be prepared to question solutions and assumptions. As one engineer has put it, ‘buildings do not fall down until they have exhausted every means of standing up’. This maxim is particularly apt for compressive structures, such as load-bearing masonry.
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Integration and coordination of mechanical and electrical systems in detail There is frequently a problem with the output from building services enginers who are not used to providing detailed design at this stage and often present only schematic diagrams. As a result, there have been numerous instances of primary distribution routes being undersized, inaccessible or otherwise impractical. If the architect has been appointed as lead designer, they need to ensure early engagement with the building services team and check coordination carefully and repeatedly. BIM procedures may make this process easier if the base model is accurate enough. There may also be a need to consider disaster mitigation, both generally and locally, such as leak detection systems or additional waterproof floors below bathrooms to catch and contain any leaks, spillage or overflow. Finalising fire safety details Fire compartmentation and fire detection, alarm and suppression systems, together with the fire engineering required to achieve safe means of escape, need to be finalised at this stage. Fire engineering is a great blessing for historic buildings and, as with structural engineering, experienced practitioners will often come up with much more elegant and less intrusive solutions than can be achieved by simply following modern codes and rule of thumb. Permanent physical compartmentation of a large building will give it much greater and long-lasting protection against devastation by fire than any management approach can achieve. BS 7913: 2013 Guide to the conservation of historic buildings highlights fire as the primary risk for all historic buildings, since the result of a major fire can be totally catastrophic and is irreversible. Finalising inclusive access provision It will be necessary to develop the argument in support of the proposed solution, particularly if it is clear that inclusive access provision cannot be achieved for the entire building. This proposal will include choice or design of appropriate signage, and should be integrated with any recommendations for explanation and interpretation of the building.
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Inclusive access Most historic buildings were designed and constructed before level and inclusive access was considered important. Ensuring long-term beneficial use for a building and easy public access will often require major intervention, but it is a challenge that should be met with creative enthusiasm. The first step is an access audit, which involves marking up plans to show where inclusive access is currently not available, then a study of use and management practice to see if the obstacles can be bypassed, followed by assessment of how much of the building needs to offer inclusive access in order to function (usually addressed by providing all facilities at entry level in the building) and finally looking at what physical changes need to be made, such as the construction of permanent ramps, platform lifts and passenger lifts. Other considerations include signage and way-finding, colour contrast, WC provision etc. but final answers are likely to comprise a mixture of management procedures and physical intervention. Given the desire to make historic buildings accessible and available to the public, the interpretation and explanation of the cultural value of the building also has its part to play. Providing effective inclusive access should be seen as a significant enhancement of a historic building and a key element of sustaining its future.
Assembling works packages At this stage, identify works packages which will be carried out by specialists and clarify the extent of their design input, particularly if it has an aesthetic element. The NBS Create specification system can be a very helpful tool in this process as it will accommodate specification in the traditional manner together with specification based on previous examples and incorporate design by the specialist. Many historic buildings were originally constructed from materials obtained locally, which are not available from any builders’ merchant or supply catalogue. Work may be needed at this stage of the design to find out what materials are readily available, which are available but with long
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lead-in times or from a single source (wrought iron, for instance). It may be better to obtain certain materials from abroad (such as structural oak from France) but equally there are materials that do not travel well (slate from Spain and China has a much shorter life span in the UK than Welsh slate). If salvaged materials are going to be used, it may be necessary to buy and store them early in order to secure the supply, but since the choice of materials is often a condition to a listed building consent it is vital to make sure that the local planning authority or any other relevant authority is happy with the selection. Be aware that natural materials such as stone may have considerable variation in colour, texture, grain etc. and so it is prudent to ask for a number of samples, as large as is practical. Managing intrusive surveys Check that the necessary consents are in place for any surveys before they are carried out. If procurement is via a design and build or similar route, the issue of responsibility for latent defects in the building will be important. All surveys, and especially intrusive surveys, should be fully documented and supported by collateral warranties in favour of the contractor, and possibly the end user. Be careful not to take responsibility for latent defects yourself and check the requisite wording with your professional indemnity insurer for any report you do make. Always be clear if there are parts of the building you have not surveyed, ideally by marking up plans and sections. Developing soft strip, salvage and protection packages These may be required as part of the listed building application. Salvage proposals in particular need careful thought, and it is worth considering retaining salvage items for disposal by the client rather than leaving it to the contractor and then being embarrassed by items potentially appearing for sale online. There are reputational issues to consider. Salvage is another area that is often controlled by conditions to a listed building consent and that can have time and cost implications.
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Moving large, delicate objects should not be left to the contractor or the demolition team – use specialists. Take the opportunity to photograph (from all sides), measure and weigh any items that are to come back into the building and make sure that each item is labelled twice, once on the outside of its protective wrapping with a copy inside the wrapping. Finalising the conservation plan The conservation plan needs to be brought to a conclusion so that it can be submitted as part of the planning/listed building consent application, but it should remain a live document, to be updated during later work stages and when the building is in use. Check whether there is likely to be a requirement to put the plan on public record (usually in the local historic environment record or local records office) and find out if they will be willing to receive it. In addition, it is worth considering publishing it on a website, but check for copyright issues regarding images, and maps in particular, before doing so. The management element of the plan is increasingly being presented in tabular format, identifying issues, policies, actions and the individual or organisation responsible for carrying out the actions. This format is useful and effective, both during the development of a major scheme and also when a building is in use.
Non-intrusive investigation In general terms, non-intrusive investigation does not change or harm building fabric and so does not need listed building consent. Examples are measured surveys, infrared scanning and photography, surface-penetrating radar (to locate voids and ferrous cramps) and ground-penetrating radar (to indicate foundations and other buried features). Borderline investigations, such as paint scrapes and taking samples of materials for analysis, probably do not need listed building consent if they are done very discretely but, if in doubt, it is always better to ask.
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Non-intrusive investigation (continued ) Some investigations, such as lifting floorboards, which probably do not need consent in a Grade II building, may be deemed to need consent in a Grade I or II* building, particularly if the boards are original and have, say, metal or wooden tongues between the boards which would be destroyed if they were lifted. Opening up where it is clear there has been previous activity is acceptable, and it is sensible to do some research into a building’s history, which will often show where previous interventions have taken place and so where fabric is likely to be less sensitive. Judgment and common sense are required.
Intrusive investigation Intrusive investigations often require consent from the local planning authority, which might well require a specific listed building consent application of its own, with knock-on effects for the Project Programme. If the investigations are discrete and small-scale in scope it may be possible to agree them by letter with the local planning authority as ‘de minimis’, but this is entirely in the authority’s hands. Again, having a clear understanding of the history and significance of the building and the relative sensitivity of its constituent fabric will help to speed discussions and maintain your credibility.
Undertaking heritage impact analysis of the proposals and reviewing mitigation measures If the impact analysis is to be part of an environmental impact statement then there are set forms and procedures to be followed. For other cases, the impact analysis should form part of the design and access statement and should respond to the relevant sections of the National Planning Policy Framework (NPPF).
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Reversibility There is an argument that repairs and changes to historic fabric should be reversible, meaning that they can be undone at some time in the future. This is an argument offered in mitigation of proposed intervention, and has some merit, so long as it is not pushed to an extreme. Reversibility is more relevant when considering which materials to use; for instance, selecting a lime mortar rather than a cementbased mortar for making repairs will prevent hard spots in masonry and discontinuity in fabric performance. Rarely will reversibility on its own be a justification for a particular proposal. There are many ways of interpreting this approach.
‘Least bad solution’ Finding the ‘least bad solution’ is an important concept. Often, when change is required, such as achieving inclusive access, there is no good solution because the building was neither designed nor built to accommodate the type of change required. Option studies are needed as usual and the final choice will probably be the ‘least bad’ solution. Remember that all types of solution need to be investigated, especially management solutions, and a good answer may not require building work or intervention at all.
Be careful to use the language of the NPPF and its supporting guidance. Check for differences in the use of language in terms of environmental impact assessment report-writing requirements and as used by other disciplines. Organising samples to support the listed building application Samples may be required to demonstrate the quality of workmanship as well as colours, choice of materials etc.
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For large projects it may be sensible to produce a complete finished room, both as an aid to gaining consent and as a way of setting benchmark standards for contractors. Increasingly, such samples are covered by conditions to a consent rather than submitted as part of the primary application.
What procurement activities are required at Stage 3? If the construction works are being let on a design and build basis, it is usual when listed buildings are involved for the developed design to be completed by the client’s design team before being released to the contractor’s team and for listed building consent to have been obtained. Ideally, the client’s team will also deal with any conditions, but this needs to be agreed on a case-by-case basis.
Locally listed buildings Each local planning authority has the power to list a building locally within their jurisdiction if they decide it is necessary or desirable. The effect is similar to that given to a building standing in a conservation area and identified as a ‘positive contributor’. It generally gives limited control over what can be done to the exterior of the building fabric, always bearing in mind the need for proportionality and reasonableness in decision-making. If a locally listed building does not stand in a conservation area and is not identified in the historic environment record it can be difficult to determine its listing status.
What programme activities are required at Stage 3? Intrusive surveys may require parts of the building to be vacated, particularly if hazardous materials may be released. On a case-by-case basis, the local planning authority may require some intrusive survey work before validating a listed building consent application. It is also important to hold discussions with the client regarding whether they would be prepared to go to appeal if planning/listed building consent
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were refused. The time allowed between a decision to refuse an application and the deadline for an appeal is not great, so if there is any possibility of going to appeal, all material that might be needed in an appeal should be included in the planning/listed building consent applications. This may mean that additional specialist reports have to be commissioned and reviewed by a specialist planning lawyer. As part of the risk management process, a view needs to be taken on the likelihood of a request for a judicial review of any planning/listed building consent decision and the possibility of an application for non-designated buildings to be listed.
Considering town planning and listed building consents at Stage 3 External stakeholder management and public exhibition of proposals It is always difficult to know when to go public with ideas and proposals, but it is a key part of the run-up to submitting applications for planning/ listed building consent for a project of any size or complexity. Design review panels like to see things at an early stage, whereas other commentators may only wish to review final proposals. Some teams deal with this by having a series of exhibitions/displays, but this approach clearly has time and cost implications. Recording feedback is important and much useful background information can be obtained once people’s interest is aroused. Review of the relevant legislation The relevant legislation is contained in the NPPF 2012 and, in particular, the sections relating to historic buildings and sites (section 12), the guidance notes to the NPPF and the Historic England advice notes. These are the documents which specifically relate to the planning/listed building process, but there are a large number of other publications which may have relevance, including BS 7913: 2013. Make sure to review local authority development plans, conservation area assessments (these should have been included in the conservation plan) and local planning authority guidance on historic building matters.
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Recheck the local historic environment record (HER) and, if necessary, contact the county archaeologist to make sure it is up to date. Design and access statement Applications for listed building consent require a design and access statement. This should be based on the conclusion from the heritage statement/conservation plan (which will also form part of the submission to satisfy NPPF paragraph 128). The design and access statement can include the heritage impact assessment or it can be a separate document. The design and access statement should outline the options explored and summarise the reasoning behind the decisions made, possibly with reference to ICOMOS guidelines or BS 7913: 2013. There should also be a section detailing how the proposals comply with the NPPF. Preparation and submission of planning and listed building applications For complex or contentious projects it will be sensible to agree the content of the applications before submission. Occasionally, local planning authorities will request a level of detail that would normally be developed in Stage 4, although this is less common since the NPPF section on proportionality came into force. The relative complexity of listed building applications can mean that validation of the application takes longer than would otherwise be expected. The client should be warned of this, and close attention paid to the validation process.
What are the Suggested Key Support Tasks at this stage? I Review and update the Sustainability, Maintenance and Operational and Handover Strategies and Risk Assessments. I Undertake third party consultations as required and conclude Research and Development aspects.
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I Review and update the Project Execution Plan, including the Change Control Procedures. I Review and update the Construction and Health and Safety Strategies. I Review all the Project Strategies previously generated. If significant parts of the works require specialist craftspeople or contractors or procurement of unusual materials it is helpful to establish their availability and lead-in times and, in certain cases, pre-order. There may be no suitable or available alternatives and these items can quickly become part of the critical path. Requests to use substitutes may require a revised listed building application, which takes time.
What are the Sustainability Checkpoints at this stage? Check whether a full formal sustainability assessment is being carried out. If so, it should be integrated with conservation and heritage concerns and be relevant to the existing historic fabric. Have an interim Building Regulations Part L assessment and design stage carbon/energy declaration been produced? Are the assessors aware of the balance that needs to be struck between compliance with Building Regulations and the often overriding requirements of listed building consent?
Planning permission and listed building consent Planning permission and listed building consent are two separate approvals needed before any substantial work can be undertaken on a listed building, and both types of approval are likely to be conditional. Although theoretically you can apply for planning approval and listed building consent separately, very few if any local planning authorities will agree to consider this. The conditions for the two approvals will generally be the same or very similar, but it is important to check them and identify the differences and the reasons for those differences.
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Planning permission and listed building consent (continued ) Conditions break down into those which must be cleared before any work starts on site; those which must be cleared before a specific item of work starts (such as approval of material samples); those which have to be cleared before the building is occupied again; and those which are, in effect, perpetual, such as a limit on noise generated by plant, and which cannot be discharged. Drawing up a schedule of conditions within these categories provides a useful tool for managing conditions, particularly those relating to listed building consent, because it holds true that failing to clear a condition before undertaking the work involved will be a potentially criminal act (for a planning condition it is simply risky but not illegal) and clearance of conditions needs to be clearly shown in the Project Programme because they are likely to be on or near the critical path, especially those which must be cleared before work starts on site. Clearance of conditions requires a set of proposals to be compiled, which will usually be developed in Stage 4, submitting the proposals for local planning authority approval, and waiting for the planning authority to process the application, which will take nearly as long as the original approval process, ie not less than eight weeks and more probably 12 weeks. However, clearance of conditions is normally handled under delegated powers at officer level, and if there is mutual respect and trust, things can be managed more quickly. The detail required for clearance of listed building consent conditions is often much greater than that required for planning permission and can necessitate design beyond that needed for Building Regulations approval and agreement of samples of materials. This is relatively straightforward to manage if the procurement route is ‘traditional’, or if the design team is appointed by the contractor from Stage 2, but requires more thought if design and build in any of its variants is in use. The same observations apply to any section 106 obligations. The overall message is that the clearance of the conditions attached to a listed building consent needs preparation, adequate time and resources and careful management. There are many pitfalls for the unwary, particularly if there are lawyers looking over your shoulder.
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Has the design been reviewed to identify opportunities to reduce resource use and waste and the results recorded in the site waste management plan? A strong argument for the conservation of building fabric is to retain its embedded energy, and many historic materials are capable of reuse.
What are the Information Exchanges at Stage 3? Information Exchanges required for Stage 3 are as follows: I at stage completion: Developed Design including coordinated architectural, structural and building services design and updated Cost Information I UK Government Information Exchange is required.
Chapter summary
3
During Stage 3 the level of detail in the design is usually sufficient to allow the project to be submitted to the local planning authority for planning and listed building consent. Listed building consent is specific to the design and detail submitted, so a greater level of detail and supporting documentation is required to allow the implications of a proposal to be considered than would be the case for a new or unlisted building. Having established detailed descriptions and analysis of the existing historic fabric, at this stage the coordinated technical strategies are developed. The focus of the design team is on the practical strategies involved in coordinating technical solutions to minimise adverse impact on the historic fabric and maximise opportunities for enhancement.
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Stage 4
Technical Design
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Chapter overview This stage is about detailed design, specification and sourcing of materials and locating specialist craftspeople. The design team working with an historic building cannot rely on catalogues of products and standard specification clauses to the extent that is possible for new build, and in a building of any complexity there are likely to be many more junction and compatibility issues to deal with. With the rather narrowly focused skill set currently available within the construction industry, the design team will have to search more widely to find the suppliers and skilled operatives necessary for work on many of our historic buildings, and their availability, lead-in times and sources of materials may influence the final Technical Design, particularly when working on a large building to tight timescales. The key coverage in this chapter is as follows: Clearing planning permission and listed building consent conditions Detail design and specification Managing the use of dangerous materials Procurement of specialist suppliers and craftspeople Completing salvage and protection packages Agreeing recording protocols Building insurance
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Introduction By the end of Stage 3 the design team will have established, coordinated and tested all the major strategies underlying the design and the range of materials and specialisms needed to deliver them should be known. Stage 4 is more about how and who rather than what. But questions of availability and deliverability may require changes to the design. Yet again, it is an iterative process, which will be speeded up by talking to or working with experienced people.
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What are the Core Objectives of this stage? The Core Objectives of the RIBA Plan of Work 2013 at Stage 4 are:
4
Tasks Tasks
Core Objectives
Technical Design Prepare Technical Design in accordance with Design Responsibility Matrix and Project Strategies to include all architectural, structural and building services information, specialist subcontractor design and specifications, in accordance with Design Programme.
Project-specific Core Objectives I I I I I
Clearance of planning permission and listed building consent conditions. Carrying out intrusive surveys. Preparing samples and mock-ups. Completion of the detailed design and specification. Preparation of tender packages. Manage the clearance of planning permission and listed building consent conditions
It is unusual for a listed building consent not to have any conditions, however detailed the application. The wording of the conditions can have a significant impact on programming, particularly those that require written clearance before any work can start on site.
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Management of the clearance of conditions is a key task at this stage and may require regular monitoring and review. It should also inform the risk analysis, if there is one. Work up details and specifications appropriate to the historic fabric being worked on Historic buildings which have been altered, adapted and repaired over many years tend to have many more areas that require individual detailing and specification than would be the case for a new or relatively recent construction. Such detailing requires more site time and a clear understanding of the technical issues involved. Standard details and specifications have to be reviewed and usually adapted, and existing detailing often needs to be improved where there is evidence that it has failed in the past; for instance, providing overflow weir outlets to rainwater hopper heads and checking the capacity of existing rainwater disposal systems. Achieving this in a way that is effective without being obvious and intrusive can be a considerable challenge in design terms and requires creative and flexible thinking. It is important to understand historic building materials and construction techniques – many modern materials and approaches to detailing may be inappropriate for historic fabric.
Ancient recipes and sources of materials Prior to the construction of the canal network in Britain, most buildings, even large ones, were built using locally sourced materials because of the sheer difficulty, and hence prohibitive cost, of transporting large quantities of bulky, heavy materials, such as brick, stone, lime, sand and gravel. Vernacular architecture is often described as buildings made from locally sourced materials whose design has evolved empirically to make the best use of those materials. Consequently, build times were often much longer than we would expect today and a much longer term view of the construction process was adopted than we are used to. At Norwich Cathedral, for example, the first phase of building was deliberately stopped and roofed over after 80 years of construction, in order to allow the building to settle,
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Ancient recipes and sources of materials (continued ) while a similar volume of contemporary building at the nearby castle was completed in 20 years. Of course, an alternative explanation for the hiatus could be they simply ran out of money at that point – Cologne cathedral wasn’t completed until the late nineteenth century (an early example of lottery funding). The shift away from an empirical approach passed on by example and word of mouth (as in the medieval trade guilds) came with the Renaissance, when published pattern books and theoretical studies started to proliferate. As printing became more widespread, these publications were joined by ‘builder’s companions’ which recorded what amounted to good practice and could include such information as recipes for mortars and plasters. However, caution must be exercised if considering applying techniques from such sources as there was formerly no standardisation of type or quality. Moreover, successfully mixing and applying a product such as a lime mortar is dependent on the source of the materials, how and when they are prepared (whether the lime has been matured over winter or not), the method of mixing and how they are used (preferably not in winter). Additionally, such mortars rely for their performance on material physics as well as chemistry, in terms of particle size, and the use of additives can be important. The use of ordinary Portland cement (OPC) in mortars is a case in point. Ministry of Works recipes used cement as an additive to essentially lime-based mortars in order to promote a fast set, but those recipes do not work well today. The reason for this appears to be that modern OPC is too finely ground and too consistent in its particle size compared to mid-twentieth century OPC, such that modern OPC clogs the air spaces necessary in a good lime mortar for its long-term carbonation and may hinder water vapour movement. So, treat old recipes with caution unless you can match the source and type of its constituent materials very accurately. Because of the way in which materials such as a lime mortar will change over time, care is also needed in interpreting materials analysis – the chemical composition of a mortar now is unlikely to be the same as the mix when the mortar was first laid. It is vital to recognise how much you don’t know and act accordingly.
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Ordinary Portland cement (OPC) It is arguable that for low-rise compressive structures OPC-based mortars are less suitable than lime-based mortars. OPC requires much higher furnace temperatures than lime during manufacture, is not easy to produce locally and, unlike lime mortar, cannot easily be reused. OPC mortars tend to be made too strong, are brittle, do not self-heal and do not absorb and release water vapour in the way that a lime mortar can. OPC-based mortars probably became widely used because they set more predictably and more quickly than lime mortars and so reduce risk for building contractors who are working within a tight programme with penalties for being late. Using OPC in mortars and plasters for historic buildings is currently held to be anathema.
As far as possible, materials used should match those already incorporated in the building but, again, with care and close observation. Some materials, for instance hydraulic lime, rely for their performance as much on the way they are prepared and applied as on the specification of component parts or materials. General descriptions can also be misleading for the inexperienced. While both milled lead and cast lead are used for roofing, they will be specified, and probably detailed, differently as their properties and performance are not identical. Experience of inspecting and assessing historic buildings provides a very important background for the proper detailing and specification of work, both repair and new work. Some work cannot be finally detailed until the building is opened up, and there will inevitably be surprises. It is sensible to keep a record of decisions as they are made, and design development notes are a quick and effective way of doing this, particularly if the person who details and specifies the work does not carry out inspections when on site. Sketches and annotated photographs can make a very effective contribution to this process and can be used in specification and tender documents.
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It is rarely possible to repair and update all details at once, and detailing and specification should take account of the point which a particular building element has reached in its life cycle, as well as the cost of gaining access to carry out repairs in the future. If work has to be prioritised or phased there should be an agreed strategy, such as doing all high-level work necessary to maintain the building in a wind- and weathertight condition for the next 30 years. The client and users should be made fully aware of the possible consequences of the strategy being followed.
Dangerous materials Many forms of appointment prohibit the use of dangerous materials in design and construction. Unfortunately, lead is on the list of materials to avoid, despite its use being almost essential for most historic buildings, as roofing, flashings, in leaded light glazing and elsewhere. It is reasonable to insist on replacing lead water pipes and to design out instances where lead might be ingested orally (which is why white lead paint is no longer used). There are some other materials that may have similar issues, and there are many misconceptions about historic building materials such as lime. If in doubt, talk to people who use these materials and see how they approach the problem.
Dangerous practices Many fires in historic buildings have been caused by ‘hot work’ on site. Some people consider it good practice to ban all hot work on the building itself, only allowing hot work at a specified distance away from the building, if at all. In any case, there should be a regime of hot-work permits and daily inspection at the end of the day by whoever has the role of site supervisor. Hot work includes not just welding and work with naked flame, but also the use of cutting and grinding wheels. Continue intrusive surveys as required Sometimes surveys are unable to answer all questions and show that further investigation is necessary. Once listed building consent has been obtained, it is generally much easier to carry out intrusive surveys and undertake any opening up; for
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instance, checking for voids around the frame when upgrading the fire performance of existing doors. Samples and mock-ups of materials and workmanship Samples of materials and mock-ups of construction details are an important part of the architect’s toolkit when working on a historic building. This is a particularly important activity when matching the appearance of existing materials whose original source is not known or no longer exists. It is also often the case that, even if the correct materials can be sourced, the way they are treated or worked on has to be checked. Listed building consents often have conditions requiring samples to be approved or mock-ups of key details to be provided, and time and resources must be set aside to deal with this. Prepare tender documents for work packages While normal NBS-type specification clauses may be effective for large projects, it is often better to specify work on smaller or more intricate projects by scheduling, often on a room-by-room basis. The choice between full-blown specification and the use of descriptive schedules also depends to some extent on the likely capabilities and experience of the workforce which will carry out the work. There is also a role for specification by performance, although obtaining listed building consent for this may be difficult, and for specification with design input, typically by craftspeople or suppliers who know far more about their skill or trade than you do. Requesting a method statement from craftspeople or suppliers is not an unusual requirement but it should not be considered a substitute for careful detailing and specification. Salvage and protection packages It is not uncommon for listed building consent to have conditions requiring specific elements to be taken out intact (salvaged) and then either stored, reused or disposed of in a controlled manner. A room gazetteer is a useful tool for managing this.
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It is also good practice to detail how vulnerable building elements will be protected – typically casing fireplaces, protecting stair surfaces and handrails, and protecting fine doors and windows. The threats to be considered are various; theft obviously, but also simple things like unlocking doors, so that people will not have to kick them open. This issue may be covered in the contract preliminaries, but a specific set of proposals in a package is more reliable and easier to enforce.
Proposals for recording A key part of proposals for salvage and protection will be a record of the items concerned. There are four recognised levels of recording, the simplest of which is a photographic record and the most complete being photographs, measured drawings and a comprehensive written assessment (a mini conservation plan). The tender package should be clear about who is to carry out such recording, what format it will be in, how and when it will be presented and where it will eventually be kept.
What procurement activities are required at Stage 4? It is important to confirm the availability and sourcing of key materials, such as facing stone, and consider reserving supplies in advance if there is any chance that they might become unavailable.
Procurement and the best form of contract The different forms of procurement for construction work are largely concerned with the transfer of risk and responsibility. The ‘traditional’ form of building contract retains all design liability and decision-making responsibility on the client’s side of the contract and is generally seen as the most appropriate form of contract for work on historic buildings. This is largely because the control over detail, which is so important when working on historic fabric, and the response to discoveries as the building fabric is opened up, stays with the client team.
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Procurement and the best form of contract (continued ) However, many of the specialist trades and conservation techniques can only be procured by performance specification and agreed method statement, such as replacing silk wall linings, renovating a Georgian fanlight, recasting lead roofing. So, much depends on the completeness of the design and the level of detail that can be supplied by the client design team to the construction team when choosing a procurement route. Design and build is a possible option, but can only be recommended when the nature and condition of the historic fabric is well known and understood and the work to be undertaken is fully designed and coordinated, probably closer to the end of Stage 4 rather than Stage 3. Sometimes a simple day works contract may be most costeffective option, but this approach requires a client with monetary reserves who trusts both their design team and the appointed contractor(s). New forms of contract and types of specification (such as those found in NBS Create) may make this an easier issue to address, but as long as the risk of expensive unforeseen issues is perceived as being very high when dealing with historic buildings, the ‘traditional’ contract forms are more likely to be considered the most effective practice, even covering aspects such as recipes for mortars and plasters.
The design responsibility of specialists in both the design team and the contractor’s team needs to be clearly established and this is also the time to longlist and review suitably experienced contractors. Confirm the use of accredited and experienced specialist contractors and tradespeople with skills relevant to the project and building in hand. Skills accreditation schemes for crafts- and tradespeople should be used wherever feasible. Experience is very important when dealing with historic buildings and tender evaluation criteria should recognise this. It should also be borne in mind that there are very capable firms specialising in conservation work who do not necessarily fit into the standard construction contract model.
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If the project involves ‘known unknowns’ or uncertainties, discuss and agree the use of provisional and general contingency sums, and establish the mechanism for controlling their use and expenditure. The procurement route chosen may dictate how this is done, and the previous comments on latent defects (Stage 3, see page 83) and prioritising of work should be borne in mind. In a traditional form of building contract, consider whether naming or even nominating subcontractors is advisable or whether the use of multiple contracts would be a better option. Building insurance Different forms of building contract have different requirements for insurance during the building works. Make sure that the client understands whether or not they have to maintain insurance and that, if they are responsible for insuring, they have checked whether the cover is suitable and adequate. Depending on the type and size of building, check whether the client’s insurers will want to review the design or completed building works and whether they have any specific requirements (such as building-safety fire standards rather than life-safety).
What programme activities are required at Stage 4? Clearance of conditions The time needed for this activity is often overlooked by project managers and programme writers but the risk of getting this wrong can be considerable, particularly if the project is at all controversial or being undertaken in the public eye. In general, there are four types of condition to a listed building consent: I those that must be cleared and confirmed in writing before any work starts on site I those that must be cleared before a particular element of work starts on site (typically agreeing materials samples or providing a method statement) I those that must be cleared before the building is occupied
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I those that cannot be cleared but which continue for the foreseeable future (typically conditions controlling aspects of the building in use, such as noise generation). The first type of condition, which ought to be unusual but is actually becoming more common, has the greatest impact on programme as it can potentially delay the start of work on site, with all the attendant costs that delay can entail. The current process for clearing a condition is the same as that for making a listed building application, and can take as long to reach a determination, so it is important to schedule conditions as soon as they are known and allow time within the programme for preparing applications and for their clearance. It is unlikely that clearance of conditions will go back to the planning committee and normally such issues are dealt with at officer level, so building and maintaining a positive relationship can be very helpful. Clients and their lawyers can take different views on whether to proceed on the word of an officer or to wait for formal approval in writing, and this is their decision not yours, but you should remind them of the potential consequences of carrying out work prior to formal approval, which are: I issue of a stop notice I requirement to undo any work carried out and reinstate and I in extreme cases (typically unauthorised demolition), prosecution for criminal offence. There are likely to be many more singular and abnormal details in an existing historic building. Weathering details in particular need great care and attention and cannot be rushed.
Considering town planning and listed building consents at Stage 4 The clearance of conditions must be closely tracked and recorded. It will not be possible to fully clear certain conditions until work starts on site, and most permissions contain a condition regarding ‘discoveries’. Procedures for recording, soft strip and opening up and for the protection of key features, such as fireplaces, must be agreed and established.
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What are the Suggested Key Support Tasks at this stage? I Review and update the Sustainability, Maintenance and Operational and Handover Strategies and Risk Assessments. I Prepare and submit the Building Regulations submission and any other third party submissions requiring consent. I Review and update the Project Execution Plan. I Review the Construction Strategy, including sequencing, and update the Health and Safety Strategy. I Review and update the conservation plan and heritage impact analysis.
What are the Sustainability Checkpoints at this stage? Assuming that the Sustainability Checkpoints in the RIBA Plan of Work have been completed, confirm that they have taken into account the condition and performance of the historic fabric and will not cause the fabric any harm. Ask questions such as ‘Is the building fabric still able to breathe?’ ‘Is the level of insulation provided and its location appropriate?’ ‘Has full account been taken of the retained embodied energy?’
What are the Information Exchanges at Stage 4? Information Exchanges required for Stage 4 are as follows: I at stage completion: completed Technical Design of the project I UK Government Information Exchange is not required.
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Chapter summary
4
During this stage the detailed design is completed and the process of specifying and sourcing the required materials is under way. This chapter has stressed the necessity of locating and engaging the specialist craftspeople required to undertake the project and the importance of sourcing the correct materials to complement the existing building fabric. Clearance of conditions to planning permission and listed building consent will start, together with detailed recording of the historic fabric.
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Stage 5
Construction
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Chapter overview This chapter looks at some of the issues which may arise once construction work is under way. It seems almost inevitable that there will be unexpected finds and surprises as work progresses, which will require a rapid and informed response on the part of the design team. The procurement route chosen will determine the ability of the design team to instruct, advise or simply observe. The key coverage in this chapter is as follows: Protecting the building Managing changes to proposals Dealing with discoveries Checking for compliance with legal consents Engaging with specialists Recording the building in detail, discoveries and the work carried out
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Introduction The key question at this stage is how much time the design team should expect to spend on site. This will always be more than would be allowed for on a new build project or work on less complicated older buildings but will largely be dictated by the procurement route chosen. There will be surprises and problems to solve once the building is opened up and work is under way. These may be local or they may be more general. They may require detailing to be revised or, in the worst case, redesign. This is the point at which it becomes clear if enough investigation and analysis was undertaken in earlier stages and whether those investigations were focusing on the right places.
Time on site The architect should expect to spend much more time on site working on an old building than they would if inspecting the construction of a new building, regardless of the procurement method selected. This should be anticipated in the fee proposals and resource management. When the RIBA published separate fee scales for work on historic buildings, time during construction was given as 40% of the fee for full service, compared to 25% of the fee for new build.
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What are the Core Objectives of this stage? The Core Objectives of the RIBA Plan of Work 2013 at Stage 5 are:
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Tasks Tasks
Core Objectives
Construction Offsite manufacturing and onsite Construction in accordance with Construction Programme and resolution of Design Queries from site as they arise.
Project-specific Core Objectives I I I I
Protection of the building. Responding to discoveries on site. Recording discoveries on site. Checking that details and specifications are being followed and revising them when necessary. I Passing on information at handover.
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Core Objectives in detail Protecting the building during construction Protection of the building is often procured through a performance specification backed by a request for a method statement. It is difficult to be prescriptive without forcing the contractor into a particular work sequence or programme, which could have other consequences in contractual terms. This means that time and attention have to be given to checking the contractor’s proposals and making sure that they work in practice, not only at site set up but also as work progresses. Obvious key activities are soft strip, salvage and protection measures. Other important aspects to consider are: I site security I keeping the building wind- and weathertight (even if the roof is being taken off and replaced) I water management (to control rainfall and excess building water) and I structural stability. Thought must also be given to the best way to assist the structural engineer, particularly if the work requires deep excavations or underpinning work, optimum scaffolding procedures, asbestos removal and opening up. Asbestos removal is particularly difficult to monitor because it is usually carried out inside tenting and can be quite destructive. Uncoordinated drilling of holes for MEP installations can be very destructive, and on many sites it will be sensible to have a clear policy of the maximum size of holes that each subcontractor can make without prior approval, a regular review of where holes are needed before they are drilled and a clear understanding of the size of hole that will need specific listed building consent. It is also worth checking that subcontractors understand where holes and notches should be located in wooden beams and joists, as historic structures often have less margin for error in this respect. Ideally, the building will have been investigated in sufficient detail to identify and reuse existing routes and so minimise perforation. There are also related issues of maintaining fire compartmentation and acoustic separation.
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Hazardous materials Older buildings can often contain materials which we now regard as hazardous. Typical examples are asbestos, which was widely used for many things as it was formerly thought to be a wonder material; lead, which is found in paint, pipework and plumbing; and arsenic, which can be found in wallpaper dyes and some green glazed tiling. Certain materials, such as asbestos, have to be encapsulated or removed by specially trained operatives; others, like lead, are carefully removed from areas where they might be ingested; and some, such as arsenic in glazed tiling, are left alone and untouched, so that they remain encased. There are also materials, such as glass fibre quilt, whose modern forms are regarded as safe but which in their early form could be hazardous, as the glass fibres then were not thoroughly bound with resin, as is now the case, and they could cause eczema or breathing problems. There may be biohazards, such as anthrax which, it is alleged, may be found in the animal hair incorporated in plasterwork installed from around 1900 up to the First World War, and more normal biohazards, such as dried sewage from leaking soil pipes and foul drainage joints, and dust. The architect needs to be aware that any old building can contain hazardous materials and when inspecting them be prepared to use disposable overalls, gloves and a dust mask. You need to check your conditions of appointment, which may prohibit the use of lead, and make sure that there is a clause which allows you to use lead for, say, roofing even though you would not use it for paintwork or drinking water pipework. There are also issues concerning asbestos removal, which is often carried out inside an obscure tented enclosure so it is not apparent whether anything else has been removed or damaged until the operatives have finished, which may have consequences for listed building consent. Be aware, be careful.
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Hot work The use of flames or hot work has destroyed many an old building. Even injudicious use of strong lighting, which can overheat nearby fabric, or the careless use of a disc-cutter on ferrous metal can cause a fire. Buildings are particularly vulnerable to fire while they are construction sites, and in large buildings setting up temporary compartmentation and escape routes may be worthwhile. Many authorities now ban all hot work inside their buildings and expect the design team to specify systems and techniques that do not require hot work, or, if it is unavoidable (for example, lead welding), to carry out hot work well away from the building in a secure designated area. Make sure there is an appropriate clause in the prelims or your specification giving full control of hot work.
Discoveries It is not unusual to make discoveries when working on old buildings, but it is almost impossible to predict what will be found. If human remains are discovered, the coroner should be informed and, depending on the circumstances, an archaeologist may become involved. Unexpected wall paintings, priest holes and similar finds are exciting, but usually discoveries will be more mundane, such as blocked doorways, old wallpaper or redundant services. All of these discoveries will help to improve your understanding of the building and its history. The key thing is to make sure that the contractor and their team tell you about discoveries as soon as they are found, that they stop work in that area and that a photographic record is made as soon as possible. The architect needs to be available to attend on site and inspect as soon as possible and to be flexible about any lost time, otherwise people may be reluctant to tell you if they do find something.
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Scaffolding Care needs to be taken when considering working access to historic buildings. At times it may be possible to avoid the expense of a full scaffold by using abseilers, hoists etc., but there will always be a point at which full working scaffold is necessary. Indeed, for some buildings the forward maintenance planning follows the typical 30-year scaffolding cycle almost exactly because the cost of providing working access can be greater by far than the individual maintenance and repair tasks envisaged. Normally, scaffold is attached to the building via fixing points inserted into the fabric (using Hilti ties or similar fixings). These usually need listed building consent and on some buildings may not be acceptable at all. The architect should also specify whether or not the ties are to be removed at the dropping of the scaffold and should check that this has actually happened. Specifying freestanding scaffold may seem an easy way out, but such an arrangement usually requires a lot more room for external bracing and will almost certainly be much more expensive. If the work requires masonry scaffold, ie strong enough to carry the weight of large stones, both those which have to be removed and those due to be built in, there may be limitations on the number of lifts that can be worked at any one time. This will have a direct impact on programme and hence cost. On very long jobs it can be cheaper to buy and then resell the scaffold rather than hire it, paying separately for erection, adjustment and dismantling.
It is common practice to have a regime of hot work permits, or a complete ban on hot work within a specified distance from the building. The risk of catastrophic damage by fire during construction is very real and for highly significant buildings it may be necessary to install temporary fire detection and alarm systems during the construction period and to carry out escape and fire-fighting drills. On large buildings, temporary fire compartmentation should also be considered. Ensuring that historic fabric suffers no unnecessary damage during work on site and that materials and workmanship are commensurate with the
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requirements of the historic fabric are vital considerations throughout the project. Damage can be both physical and aesthetic. Take the example of electrical cabling: overzealous chasing can cause considerable physical damage; however, surface-mounted trunking would cause worse visual/aesthetic damage. Even if an acceptable route for chasing can be found, long-term damage can be caused if the wrong materials are used for making good. Ideally, a cabling route can be found that does not require chasing or surface trunking but you will have to work within the current electrical regulations. This falls within the territory of finding the ‘least bad solution’, and such decision-making should not be left to the contractor or their subcontractors. Some local planning authorities will expect such issues to have been sorted out as part of the listed building consent process, at least to the extent of knowing the cable routes and having a clear strategy for their installation. How something is to be installed may well determine what can be installed and where it can be located. This is why agreeing the sensitivity analysis is important, so that the right level of challenge and complexity is used where it is necessary. For instance, using VESDA (very early smoke detection apparatus) fire detection in rooms with ornate plaster ceilings rather than surface-mounted detector heads, but accepting surface-mounted heads in less sensitive rooms with plain ceilings. Managing changes to proposals The architect should allow time for being available to review and instruct changes when discoveries are made on site. It is very difficult to engage in such detailed decision-making unless you are on site. It is equally important to build a positive working relationship with the site management and key operatives so that they understand the heritage issues and know when to call you in to look at what they are doing, but you will need to be positive and take responsibility for decisions made. The range of discoveries possible is very wide and can cross a number of disciplines, so be prepared to bring in other members of the team to review what is found and to seek their advice on how best to respond. Above all, make a detailed record and keep your client informed.
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Add site-specific heritage issues to the site induction process and present to senior management Where the site is large enough to have regular site induction sessions it can help to raise general awareness of heritage issues by adding a section to the induction covering the key issues on the particular site. It can also help to present the conservation plan to senior site managers and to make sure that they understand the consequences of a building being listed. The more clearly people understand the significance of a building, the more likely they are to respect it, and to work for it rather than fight against it.
What procurement activities are required at Stage 5? During this stage the selection of specialist subcontractors and suppliers will be confirmed. If procurement is not following the traditional route this may be out of your control, unless specific requirements for your approval have been written into the contract/Employer’s Requirements. Check the skills accreditation of the workforce. If a contractor has said that they will be using accredited workpeople, make sure that they do. Operate an early warning system for variations to the contract. Working on an existing building, it is almost inevitable that there will be variations, discoveries and changes. Clients and cost managers need to be kept informed and a system of early warnings, ie raising the possibility of change or variation as soon as you are aware of it, helps to manage the issues and prioritise expenditure of funds.
What programme activities are required at Stage 5? Allow for more time on site and more frequent site visits than would be usual for new build. Some sites are so complex that full-time site presence is required for at least part of the construction period. It is not unusual with a traditional contract for 40% of the fee to be used in this stage, depending on how much access there was to the building and how extensive the surveys and investigations were during Stages 3
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and 4. A lean management approach is a good habit to adopt. This means identifying what you need to do to finish and how long that will take, rather than recording what you have already done. Careful management is key to avoiding any wastage of your time.
Considering town planning and listed building consents at Stage 5 Continue to manage the clearance of planning and listed building consent conditions and make sure that the construction team are fully aware of them. It is always surprising how many members of the construction community do not understand what a listed building consent does and does not allow you to do. Organise site visits for local planning authority officers and Historic England as required to give them confidence that heritage issues are being taken seriously and are being dealt with properly. Once officers are confident that the building is in a ‘safe pair of hands’ it becomes much easier to discuss issues and get their approval quickly in response to changes and discoveries on site.
What are the Suggested Key Support Tasks at this stage? Support tasks are now focused on health and safety on site, and then in use, ensuring that the project handover and post-occupancy activities determined earlier are properly delivered. From a conservation perspective, the main tasks will include: I Managing and recording salvage and disposal operations during demolition, if this work has not been delegated to the contractor or a specialist. I Managing the recording of the fabric as found and as built. Contractors and subcontractors will often be undertaking this task anyway, but you should monitor their output and obtain any records that need to be added to the conservation plan.
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I Updating the conservation plan. I Drafting a conservation handbook for handover at completion, if this is part of your brief.
What are the Sustainability Checkpoints at this stage? The main task from a conservation viewpoint will be to check that changes made in response to discoveries on site have not had an adverse impact on the sustainability criteria being delivered, that they have not had an impact on the Construction Strategy or Handover Strategy and that information passed on is properly correlated and coordinated.
What are the Information Exchanges at Stage 5? Information Exchanges required for Stage 5 are as follows: I at stage completion: ‘As-constructed’ Information and a record of discoveries I UK Government Information Exchange is not required.
Chapter summary
5
This chapter has examined some of the issues which may arise once construction work is under way. Dealing with unexpected discoveries is an essential aspect of this stage and the ability of the design team to respond to discoveries on site is, to a large extent, determined by the choice of procurement route. The amount of time that the architect must commit to spending on site will inevitably be much greater than on a new build and this should be reflected in the fee structure. It is essential that a complete record of all discoveries on site and how problems have been addressed is passed on to whoever owns or manages the building.
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Stage 6
Handover and Close Out
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Chapter overview This is an important stage for conservation projects and many feel it is a moral duty to make available and pass on as much information about the building as it is possible to compile, because so much tends to be found out or confirmed when a building is opened up and such opportunities may present themselves only once in a generation or even less frequently. Normally the information is passed on to the client, the building owner or their management team, but there may also be instances when some material at least should go on public record. The key coverage in this chapter is as follows: Updating records and the conservation plan Confirming compliance with listed building consent conditions Checking reinstatement after removal of protection measures Confirming the location of salvaged and stored material Issuing records of the building
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Introduction The main additional considerations for the design team on a historic building project at this stage compared to a new build project are the extra requirements for detailed recording of what has been found and how issues have been dealt with while construction work was under way. There may also be a wider requirement for advice on the maintenance and upkeep of the fabric when in use than would be expected for a new build and some funding bodies will expect maintenance advice to be incorporated into the conservation management plan. It is also possible that what has been found on site will lead to a review of earlier work, such as the conservation plan.
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What are the Core Objectives of this stage? The Core Objectives of the RIBA Plan of Work 2013 at Stage 6 are:
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Tasks Tasks
Core Objectives
Handover and Close Out Handover of building and conclusion of Building Contract.
Project-specific Core Objectives I Handing on the updated conservation plan. I Handing over records if they have not been added to the conservation plan. I Giving advice on future maintenance.
Core Objectives in detail The conservation plan will need to be updated both to reflect discoveries on site and to record work carried out. Some funders will expect a management and maintenance plan to be produced, which will elevate a conservation plan into a conservation management plan.
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Ensure that building owners, users and managers have all the relevant heritage information and a clear understanding of its cultural value. The conservation plan is a suitable vehicle for achieving this, together with site walk-rounds and presentations. As with contractors, the users and occupiers will respect the building and its heritage more if they understand its significance. If the conservation plan has been developed into a management plan, or if a management and maintenance plan (conservation handbook) has been produced, this should be presented to and discussed with the facilities management team and/or the user, particularly if work on site has had to be prioritised and it is known that further work will be needed in the future. Check the condition of all elements of the building that were covered for protection during the construction phase and advise if any remedial works are necessary. This should be done before handover and a photographic record made. Experienced contractors will probably do this themselves, but you should check their record and have your own copy. Check that arrangements for public access and interpretation and explanation of the building are in place. Remind the client to make sure that building insurance cover is in place before the contractor leaves site.
What procurement activities are required at Stage 6? Soft handover or practical completion? If a traditional form of building contract has been used, then there will be a requirement for a Certificate of Practical Completion, with all the known issues that surround that certificate. In the case of partial handover, and if the commissioning of MEP equipment can only be done with the building in use, it becomes increasingly difficult to give any single date at which practical completion can be said to have been achieved. This problem can be worse in historic buildings where traditional materials and techniques are used, which can have longer setting and drying out times.
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You should factor in any delay in obtaining written clearance of planning and listed building conditions, final Building Regulations approval etc., particularly if these include any matters outside the main contractor’s control, in which case the decision becomes yet more complicated even if a clear definition or checklist has been given in the preliminaries detailing what must be achieved to certify practical completion. Increasingly, the transition from being a building site under the control and responsibility of the main contractor to being a building fitted out and in use now takes months rather than days and the process of handover is described as a ‘soft landing’. This is not a new concept – there is evidence that, historically, drying out a building after construction work and before occupation could take anything from six months to two years. Problems frequently arise today from buildings being dried out too fast and heated up too much. Although the architect will have little control, and possibly little involvement, in this process, a slower transition from construction site to being in use
Recording Keeping accurate records is important because, to some extent, any work carried out on a building destroys evidence of its past. In addition, there is usually much better access to the building during works, both from scaffolding to get hands on with the external fabric and through opening up of the building fabric to reveal what lies beneath the surface finishes. Everybody takes lots of photographs, but proper recording requires them to be organised systematically, preferably showing the date on which they were taken, the location of the shot, when and especially why they were taken. Other forms of recording include measured survey, sketching (which can sometimes be more informative than photography), taking samples, materials analysis and gathering oral histories from those who have used the building previously.
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Recording (continued ) Historic England publishes advice on record keeping which defines different levels of recording. Sometimes a listed building consent condition will specify a level of recording, and the architect should be aware of the work required for each level and make a considered assessment of whether they are the person best suited to carry out the task. Records should not languish in the architect’s filing system. Copies should be offered to the local records office, local museums etc., and a copy should be included in the operation and maintenance manuals prepared during this stage.
is generally beneficial, allowing the building fabric to adapt gently rather than suddenly. This is particularly important if a central heating system is installed. This is also a period, particularly if there have been a lot of wet trades or extensive below-ground structural work, when latent defects (such as dry rot) will appear or reappear and arguments about cracking and responsibility for making good will almost inevitably arise. Do not forget to check the location and condition of any items salvaged and retained, and that all items scheduled for reinstatement are actually back in place. The architect can play a key role in managing the client’s and contractor’s expectations.
What programme activities are required at Stage 6? Practical completion will be a milestone in any programme. If a soft handover is planned it should be well defined before it happens and probably needs a mini-programme of its own, but this is unlikely to be under the architect’s control or influence.
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Operation and maintenance manuals These may need to be more detailed and wide ranging than usual when handing over a listed or historic building, if only because the range of types of building fabric will tend to be greater and the methods used more particular. Some clients will ask for a full maintenance manual. If bespoke materials have been used, such as specialist paint colours, consider keeping supplies of the actual product used for future retouching as it may not be possible to get an exact match in the future.
Considering town planning and listed building consents at Stage 6 Confirm the clearance of all conditions that can be cleared. Walk round the site with local planning authority and Historic England officers to confirm that they are satisfied with the result. For larger and more complex sites, discuss setting up a Heritage Partnership Agreement between the client and the local planning
Storing salvage Occasionally, historic artefacts, such as doors, ironmongery and light fittings, are removed from use in a building but specified to be kept on site. If this is the case, make sure that there is a specific storage space, preferably kept locked, and that an inventory of contents is maintained. If the material is cased or wrapped, make sure that there are identifying tags both inside and on the outside of the wrapping. At completion of the job, check the location and condition of all salvage items and that any scheduled for reinstatement are in fact back in place.
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authority. This is a new option in legal terms, but is a technique that has been used on large and complex heritage sites for some time. The Heritage Partnership Agreement will often be based on the conservation management plan and is, in essence, a legal agreement between the building’s owner/user and the local planning authority as to what works can be carried out in future without requiring a specific application for listed building consent. Not all local planning authorities are willing to enter into such agreements, and in any case they will normally be time limited (five to ten years) and subject to review before renewal.
Preservation by record This concept comes from archaeology, where digging a site effectively destroys it. This is why archaeologists are cautious about digs or excavations and can carry that caution over into their dealings with buildings. Clearly, if historic evidence or a heritage asset may be disturbed or destroyed then it is very important to record what is found and to make that record available to others, and preferably to the public as a whole. (Be aware of ‘grey literature’, which comprises the large amount of recording and reporting which is ‘under discussion’ and not yet published. You will need to ask the county archaeologist if there is any information relevant to your site.) Architects will normally encounter preservation by record when their work involves substantial or total demolition of a historic or designated building, especially if the reversibility argument is being used. As with reversibility, preservation by record constitutes mitigation of damage, not a justification.
What are the Suggested Key Support Tasks at this stage? I Carry out the activities listed in the Handover Strategy, including Feedback for use during the future life of the building or on future projects. I Update the Project Information as required.
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I The priority during this stage is the successful handover of the building and concluding the Building Contract with support tasks focused on evaluating performance and providing Feedback to inform future projects. Fine tuning of the building services is likely to occur at this stage. I Update the conservation plan at practical completion/soft handover ready for passing on to the client and building users/managers. I Deposit the building record in the local records office or historic environment record as appropriate. The record could also be attached to the building’s health and safety manual. I If a BIM model has been used, attach as much of this information as possible to the model. I Consider publication of the project in either a learned journal or book.
What are the Sustainability Checkpoints at this stage? You should monitor the collation of the post-completion information to ensure that it is complete for the final sustainability certification.
What are the Information Exchanges at Stage 6? Information Exchanges required for Stage 6 are as follows: I at stage completion: updated ‘As-constructed’ Information I UK Government Information Exchange is required.
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Enriching the List The listing or designation of buildings is at the heart of our current heritage protection in the UK. Each building that is listed has a listing description. Originally, before it was feasible to publish photographs with listings, a listing comprised only sufficient text to identify the building. Modern listing descriptions are longer, and attempt to explain the significance of the building as well as describe the building itself. However, not many listed buildings have an enhanced list description, and most listings do not give any indication of the future potential or possibility for conserving, improving or enhancing the building. The listing descriptions need to be updated en masse, but Historic England does not have the time or resources to do this. One way to help fill the gap, and a way to celebrate good design as applied to listed buildings, is a scheme managed by Historic England called ‘Enriching the List’. The scheme works by encouraging members of the public to log onto the Heritage Gateway (www.historicengland.org.uk/ listing/the-list) and then add photographs of listed buildings to the list descriptions. This presents an opportunity to widen the appreciation of buildings and to highlight good design. Using images rather than words is positive – it is traditional for buildings to be described using drawings and images rather than words – and there are far too many words about anyway. The scheme offers broader possibilities, such as setting up a showcase and reference point demonstrating the importance of good design as part of sound conservation of buildings. It will allow people to highlight what they value and enjoy in our heritage. It also offers architects and others the opportunity to record what they have achieved and that is not currently mentioned in the list descriptions. Foster and Partners’ work at the British Museum springs to mind, together with McAslan and Partners’ at King’s Cross, and small gems such as IF_DO’s pavilion at Dulwich Picture Gallery in London.
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Enriching the List (continued ) Heritage England moderates the listings site, so you need to identify yourself by registering before you can post an image, but the system is simple and runs on the general principle of ‘be nice’. There are limits on file size that can be uploaded, but these will change as technology improves. It is also possible to pay to expanded an entry, if you want to update the words as well. This is an important opportunity for designers – and architects in particular – to showcase good design in the context of working with existing historic buildings, and for building a reference source containing good examples of what has and can be done that is publically available to all. Good design is understated in current advice on conservation and heritage. This scheme offers a chance to redress the balance and give better definition of what can be achieved to conserve and enhance our historic buildings. Please give it a try.
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Chapter summary
6
It is vital at this stage to pass on as much information about the building as it is possible to compile, because the opportunity to discover details about the building fabric beyond the external finishes presents itself so infrequently. It may even be appropriate to consider putting certain material on public record. The architect on a historic building project needs to ensure that a detailed record is made of all discoveries and their resolution while construction work was under way. More detailed advice on maintenance and upkeep of the fabric in use may be needed at handover than would be expected for a new build. It should also be borne in mind that discoveries on site during the construction phase may lead to a review of earlier work, such as the conservation plan/heritage statement.
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Stage 7
In Use
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Chapter overview This chapter looks at some of the activities which a conservation architect may be engaged in when a building is in use. The attitude to the historic fabric during this stage will be much more conservative, maintaining the status quo as far as possible. The key coverage in this chapter is as follows: Regular inspection of buildings Review of the conservation management plan Advising on maintenance and repair Reviewing the effects of changes in legislation Updating records
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Introduction Some conservation architects and design team members derive much, and sometimes all, of their workload from this stage, advising clients and facilities managers on repairs, maintenance, minor works etc., and particularly from regular inspections of historic buildings which inform forward maintenance planning and strategic thinking. This activity completes the circle and brings the work undertaken back to Stage 0.
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What are the Core Objectives of this stage? The Core Objectives of the RIBA Plan of Work 2013 at Stage 7 are:
7
Tasks Tasks
Core Objectives
In Use Undertake In Use services in accordance with Schedule of Services.
Project-specific Core Objectives I Maintaining beneficial use. I Maintaining the building fabric through regular inspection and planned programmes of work. I Enhancing the building and the wider public’s understanding of the building. I Adapting the building to change.
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Core Objectives in detail To help maintain beneficial use and promote widespread understanding of the building’s qualities and cultural value Beneficial use is key to the long-term conservation of a building or site. Broadly, it is a use which will provide the income stream necessary to maintain, repair and adapt the building in good order for the foreseeable future, so conserving it for future generations. Optimum beneficial use is either the original design use or a use which does least harm to the historic fabric. Monuments, archaeological finds, museum exhibits etc. are different, in that they no longer have a practical use and generally cannot of themselves generate an income stream. They do not usually have to adapt to change and are not expected to do so. The approach to works of repair and maintenance to such items is much more restrained than for buildings. To keep the building fabric in good condition through regular inspection leading to a planned programme of works Make sure that you understand your responsibility in taking on inspection work, define the scope of your work carefully, particularly regarding areas and aspects of the building that you have not inspected, and make sure that your written report follows the format and contains any specific wording required by your professional indemnity insurance.
Cracks Many historic buildings have load-bearing compressive structures, typically masonry or brickwork. Such structures were designed empirically, not through calculation. They often have cracks in them and a key skill for any architect working with old buildings is the ability to take a view on whether a crack or system of cracks is an immediate cause for concern or not. A good starting point is to read The Stone Skeleton by Professor Jaques Heymann, which gives a very good explanation of how
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Cracks (continued ) complex structures such as medieval cathedrals were able to be designed without calculation. More practical skills include looking closely at cracks to see if they contain dirt (in which case they are probably old and less cause for concern) and applying methods for quickly and cheaply testing whether or not the crack is live (such as a pencil mark across the end of the crack with a date beside it so that any extension of the crack will be clear at the next inspection and, if working with a structural engineer, fixing three or four cross-head screws across the crack which can be measured in three dimensions to check for movement). Some cracking is a result of thermal movement, leading to the phenomenon known as dust jacking. This is when a crack opens due to heating and dust falls into the crack, preventing it from closing again, so the crack gradually becomes wider and wider. Some cracking can be cyclical (such as that due to tidal movement on the banks of the River Thames). Changing ground conditions are a common cause, either resulting from the ground becoming sodden due to leaking drainage or through drying out. Cracks, in and of themselves, may not be an urgent cause for concern, but immediate and substantial damage can be caused if water gets into a crack and then freezes. This is why keeping water out of the building and leading water run-off away from the building is so important for its long-term conservation.
Rising damp Modern buildings are designed to exclude damp by placing impermeable barriers into the construction. Older buildings often work differently, by absorbing water and then releasing it again (breathing), and inserting barriers, which are unlikely to be entirely complete in any case, can, through concentration of any damp present, create a problem that may not have existed in the first place.
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Rising damp (continued ) Recent research suggests that ‘rising damp’ does not, in fact, exist and that most damp is penetrating damp, usually from roof run-off or failed drainage. Keep a cynical open mind when considering specialist treatments to rectify the problem. Check any ‘guarantees’ offered very carefully – they are likely to be much more limited than you expect.
Dry rot Dry rot spores are probably widespread within our historic building stock, but because they require very specific environmental conditions to become active, this is less of a problem than it might be. Water penetration is a typical trigger for a dry rot attack. Unlike wet rots, which stay where excessive water is present, dry rot will grow through structures to find new water sources, feeding off organic material on the way, and it can do this very quickly. If left untreated, dry rot will destroy timber and organic material, so must be dealt with immediately. The traditional response to dry rot was entirely destructive – to identify the furthest extent of the growth and remove all organic material up to four feet beyond it. Later techniques involve spraying with chemicals to eradicate the spores, and this approach has its place, but simply changing the environmental conditions will cause the dry rot to go dormant and desist its attack. As with damp treatments, talk to specialists but be wary of guarantees. Read Historic England’s advice notes.
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Most inspections will be visual, undertaken from ground level or where there is safe access, and do not involve opening up or intrusive investigation in the first instance. Even if you know the building, and particularly if you do not, it is essential to have a health and safety procedure in place for visiting and inspecting buildings and make sure that there is someone else on site who can assist or call for help if you have an accident. Ensure that you understand how to use ladders and other access equipment safely and do not take chances. To enhance and promote understanding of the building when possible The more people understand and appreciate a building, the more likely they are to help look after it. Enhancement includes removing negative impacts (an easy win) but positive enhancement, creating delight, is also a central part of the architect’s role. To adapt the building to change There are many types of change that can require response or alteration of a building in use, from climate change (for example, rainwater systems being surcharged by increasingly intense rainfall) to changes in legislation (such as the provision of inclusive access requirements), technology (IT in particular), expected standards (for instance, for heating and cooling), security (particularly blast protection) as well as health and safety issues.
Other species which inhabit buildings At present, there is legislation which says we should protect our historic buildings and other legislation which specifies that certain species, such as bats and badgers, require protection. The penalties for damaging buildings or species habitat are potentially severe, although the maximum fine for damaging a listed building (£20,000) is much greater than that for disturbing bats (£5,000). The problem is that some protected species inhabit historic buildings and, if left unchecked, can damage the buildings and their contents quite severely.
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Other species which inhabit buildings (continued ) In an ideal world, common sense would come into play, but it rarely does. Over-enthusiastic insistence on either set of legislation is not helpful, but almost inevitable when the regulations are managed by bureaucracy. The protection zones for protected species can be large; a special protection area (SPA) has an immediate 400m exclusion zone for any residential development (ostensibly to discourage cats!) and a 5km zone of influence. Badger sets have a 30m exclusion zone and great crested newts a 500m exclusion zone. The constraints are not only spatial but can also be used to control when work is carried out, to reduce disturbance during breeding seasons. If the site has bats, birds, badgers etc. present, the various regulations in place could technically limit the time window available for building works to a couple of weeks each year. It is not only fauna that are protected but also flora. This issue can become quite esoteric. There is a variety of lichen that has only been found so far on two church towers in Norfolk, but as there are probably only two or three people who can tell which lichen is which, how does an architect deal with this? The architect has to be aware of the building as a series of ecosystems to be treated with understanding and respect.
Minimal, elegant and invisible repair For some people this is the essence of conservation work relating to historic buildings. It requires self-effacement rather than self-aggrandisement, which some architects find difficult. However, the culture which we celebrate in protecting historic buildings is one of change, often on a grand scale, so ‘minimal, elegant and invisible repair’ is part of the toolkit, not a prime objective.
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There can also be impacts from changes in attitude and legislation not directly targeted at buildings, such as protection of bats and their roosts, nearby development and infrastructure projects. Networking with other architects who are also dealing with similar issues is a good starting point for developing a likely range of solutions.
What procurement activities are required at Stage 7? Maintenance programmes Assist in setting up a rolling maintenance programme, informed by the expected life cycles of key elements and materials. Understanding expected life cycles is an important factor in assessing a building. For example, if a lead roof with an expected life of 150 years is failing at 50 years, then either it was installed very badly or, more likely, there has been a major change in its immediate surroundings or the way in which it has been treated. The cause of failure needs to be identified and understood before remedial action is undertaken.
Cleaning the building fabric Routine cleaning does not need listed building consent, but some local authorities consider that external cleaning of, say, stonework materially affects the nature and character of the building if it removes its natural weathering and patina. In addition, using the wrong cleaning method can cause considerable damage. Often, all that is needed to clean masonry effectively is a nebuliser water spray, although this usually requires scaffolding and is a slow process. There are a number of other techniques which use very mild abrasives, poultices etc., but specialist advice is needed when considering these. The first question should always be why cleaning is needed: will not cleaning the building cause damage? Cleaning for purely aesthetic reasons has its place, but is a less powerful argument.
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Support and advise in-house facilities management teams and their term contractors. Grant aid The opportunities change all the time, but grant aid is currently available from a number of sources and the architect is generally expected to be aware of such aid and the procedures for applying for it. This process can be quite time consuming. Volunteer work Some organisations use volunteer work effectively. The architect may be asked to assist in the management of volunteers, but again this can be a time-consuming exercise and is not the same as dealing with a building contractor.
What programme activities are required at Stage 7? A 25–30-year period between major renovations and full scaffolding of the exterior is typical for most historic buildings. The approach to conservation during the periods between major works tends towards careful and sympathetic repair rather than major intervention, and may require a different attitude and skill set to those needed for major works and interventions. Prioritising work is a key activity, assessing not only levels of urgency (typically designated as required within one year, within three years, within the medium term and ‘desirable’) and the detrimental impact of not carrying out the work but also the cost of gaining access to do the work. So, if a building is to be scaffolded, it is usual to programme all work that requires scaffolding to be carried out if it is likely to become necessary before the building is next scheduled to be scaffolded, and/ or the damage that would be caused by not carrying out the repair is thought to be significant. It is important to discuss and agree repair strategies with the client and to record them. It is also important to keep abreast of improvements in access technology of specialist firms, such as abseilers, whose skills can alter the balance of priorities.
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Considering town planning and listed building consents at Stage 7 For large and complex sites, agree a heritage protection agreement, which will usually be based on the updated conservation management plan and the building manual produced at handover. A heritage protection agreement is an agreement in advance to allow certain works to be carried out, which might otherwise need specific listed building consent, so that building operators can react and plan work more efficiently without the overhead burden and time constraint of listed building consent procedures. This also helps the local planning authority, which does not receive a fee for a listed building consent application. Heritage protection agreements will normally be time limited (usually to between five and ten years) before formal review and renewal. They can be particularly effective for organisations with annual budgets who have to spend their budget allocation within a particular financial year or lose it, and for sites and buildings where the presence of protected species dictates specific time constraints. For large sites subject to ongoing changes, set up a programme of regular meetings with the local planning authority and Historic England to preview expected works and agree which will need listed building consent and which will not.
What are the Suggested Key Support Tasks at this stage? Immediately after a major programme of building work: I conclude activities in the Handover Strategy, including the PostOccupancy Evaluation, review of Project Performance, Project Outcomes and Research and Development aspects. I Update Project Information as required (a conservation management plan is always a live document) in response to ongoing client Feedback.
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In Use For government and public buildings, assist in arranging quadrennial (every four years) inspections, carried out as indicated in the current version of the Government Historic Buildings Advisory Unit publication The Care of Historic Buildings and Ancient Monuments or departmental conservation manual. For government departments, assist in the preparation of biennial reports to Historic England. For ecclesiastical buildings, assist in arranging for quinquennial (every five years) inspections, as required by the Inspection of Churches Measure 1955.
What are the Sustainability Checkpoints at this stage? I Observe the building in use. I Check for any unexpected outcomes resulting from changes to the fabric performance.
What are the Information Exchanges at Stage 7? Information Exchanges required for Stage 7 are as follows: I at stage completion: ‘As-constructed’ Information where relevant and response to ongoing client Feedback I UK Government Information Exchange may be required.
Chapter summary
7
This chapter has highlighted some of the activities which a conservation architect may be engaged in during Stage 7 In Use. To keep the building fabric in good condition it is necessary to carry out regular inspections and, although the attitude to the historic fabric will generally be conservative, enabling the building to adapt to inevitable changes will be an important aspect of the architect’s role at this stage.
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Activities during this stage account for a large proportion of many conservation architects’ workload – advising clients and facilities managers on repairs, maintenance, minor works etc. and particularly carrying out regular inspections of historic buildings which inform forward maintenance planning and strategic thinking. This activity completes the circle, bringing the work undertaken back to Stage 0, usually about every 25 years.
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Further reading Bartlett School of Architecture (1894–date) Survey of London: www.ucl.ac.uk/bartlett/architecture/research/survey-london Binney, M. and Milne, E. (1983) Vanishing Houses in England: A Pictorial Documentary of Lost Country Houses, Save Britain’s Heritage Brunskill, R.W. (2000) Vernacular Architecture: An Illustrated Handbook, Faber & Faber Cantacuzino, S. (1975) New Uses for Old Buildings, Architectural Press Charles, F.W.B. and Charles, M. (1984) Conservation of Timber Buildings, Hutchinson Clark, K. (2001) Informed Conservation: Understanding Historic Buildings and their Landscapes for Conservation, English Heritage Clifton-Taylor, A. (1987) The Pattern of English Building, Faber & Faber Colvin, H.M. (2008) A Biographical Dictionary of British Architects, 1600–1840, Yale University Press Cullen, G. (1961) Townscape, Architectural Press Feilden, B. (2007) Conservation of Historic Buildings, 3rd edition, Routledge Fletcher, Sir Banister (1963) A History of Architecture on the Comparative Method, 17th edition, Athlone Press Government Historic Buildings Advisory Unit (1998) The Care of Historic Buildings and Ancient Monuments: Guidelines for Government Departments and Agencies, English Heritage and the Department for National Heritage Hewett, C.A. (1997) English Historic Carpentry, Linden Heyman, J. (1995) The Stone Skeleton: Structural Engineering of Masonry Architecture, Cambridge University Press
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Historic England (2008) Conservation Principles, Policies and Guidance, Historic England Hunt, R. and Boyd, I. (2017) New Design for Old Buildings, RIBA Publishing ICOMOS (2013) The Burra Charter, Australia ICOMOS Insall, D. (1959) The Care of Old Buildings, Society for the Protection of Ancient Buildings Jokilehto, J. (2002) A History of Architectural Conservation, Routledge Kerr, J.S. (1985) The Conservation Plan: A Guide to the Preparation of Conservation Plans for Places of European Cultural Significance, National Trust of Australia McKay, W.B. (2005) McKay’s Building Construction, Routledge Pevsner Architectural Guides, Yale University Press: http://yalebooks.co.uk/pevsner.asp Ruskin, J. (1989) The Seven Lamps of Architecture, Dover Publications Sturt, G. (2014) The Wheelwright’s Shop, Home Farm Books The Victoria History of the Counties of England (Victoria County Histories) (1899–date): https://www.victoriacountyhistory.ac.uk/ publications-projects Vitruvius Pollio (2009) On Architecture (The Ten Books on Architecture), Penguin Books
RIBA Conservation Course reading list Set books Brereton, C. (1995) The Repair of Historic Buildings: Advice on Principles and Methods, English Heritage Forsyth, M. (ed.) (2013) Understanding Historic Building Conservation, Wiley-Blackwell
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FURTHER READING
Historic England (2013) Conservation Basics, Practical Building Conservation series, Ashgate Orbas¸lı, A. (2007) Architectural Conservation: Principles and Practice, Wiley-Blackwell
Recommended books Beckmann, P. and Bowles, R. (2004) Structural Aspects of Building Conservation, Elsevier Butterworth-Heinemann Forsyth, M. (ed) (2012) Materials and Skills for Historic Building Conservation, Wiley-Blackwell Forsyth, M. (ed.) (2014) Structures and Construction in Historic Building Conservation, Wiley-Blackwell Historic England (various dates) Practical Building Conservation (10 volume series), Ashgate I Conservation Basics I Mortars, Renders and Plasters I Stone I Timber I Metals I Glass and Glazing I Concrete I Earth, Brick and Terracotta I Roofing I Building Environment Watt, D. (2007) Building Pathology: Principles and Practice, Blackwell
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Conservation glossary Beneficial use
Curtilage
The use to which a building may be put to generate an income stream capable of sustaining the building’s operation and upkeep in good order for the foreseeable future while maintaining the building’s cultural significance.
Curtilage can be defined, for the purposes of the listed building legislation, as an area of land around a listed building within which other buildings pre-dating July 1948 may potentially be considered for listing.
Conservation area
This statement, required for obtaining listed building consent, details the proposals for the project and its impact on the building fabric.
An area designated by the local authority or Historic England for its architectural or historic interest within which permission must be sought before making alterations to a property, demolishing a building or removing trees. Conservation area assessment A report published by the local planning authority identifying all designated assets within a given conservation area.
Design and access statement
Designated asset Items, such as listed buildings, buildings in a conservation area and scheduled monuments, to which heritage protection measures currently apply. Ecclesiastical exemption
See Heritage statement
Ecclesiastical buildings belonging to certain Christian denominations are exempt from some provisions of the Planning Acts, including the need to apply for listed building consent, and have their own arrangements for handling changes to historic buildings which provide the same standards of protection as the secular system operated by local planning authorities. Ecclesiastical buildings are church buildings which are currently used for worship or are now vacant and have never had any other use.
Cultural value
Enabling development
An assessment of the architectural/ aesthetic, historic, technical and social significance of an asset, usually described in a statement of significance.
Development which falls outside the scope of existing planning policies but which is needed to secure the future of a particular heritage asset.
Conservation area management plan A document that details the steps deemed necessary by the local planning authority to be taken to ensure the conservation area’s preservation. Conservation deficit The sum realistically considered to be necessary to secure a specific heritage asset. Conservation statement
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Enhancement In conservation terms, this involves removing negative impacts from a heritage asset and maximising opportunities to promote its beneficial use, such as by implementing effective inclusive access measures. Heritage asset Part of the historic environment that is valued because of its historical, archaeological, architectural, artistic or social interest. Heritage protection agreement An agreement in advance to allow a defined range of relatively minor and routine works to be carried out by building owners without having to apply for listed building consent every time, allowing building operators to react and plan work more efficiently without the overhead burden and time constraint of listed building consent procedures. Heritage receptor A designated heritage asset (typically a listed building) which is affected by changes to the site or building being assessed, sometimes by direct physical impact, but more usually indirectly through effects on view and setting.
identified and to prepare detailed, costed management proposals. Historic England The statutory body responsible for maintaining the Statutory List of Buildings of Special Architectural or Historic Interest in England. The corresponding bodies for the rest of the UK are Cadw (The Historic Environment Service of the Welsh Government) in Wales, Historic Scotland in Scotland and the Northern Ireland Environment Agency (NIEA) in Northern Ireland. Historic environment record (HER) HERs are information services, maintained and managed by local authorities, that provide access to comprehensive resources relating to the archaeology and historic built environment of a defined geographic area. They contain details on local archaeological sites and finds, historic buildings and historic landscapes and are regularly updated. The information is usually held in a database with a digital mapping system. Listed building A building which has been judged by Historic England to be eligible for inclusion on the Statutory List of Buildings of Special Architectural or Historic Interest.
Heritage statement
Listed building consent
Summarises the results of analysis of a site’s cultural significance, describing the significance of any heritage assets affected, including any contribution made by their setting. A heritage statement is required by a local authority prior to determining applications for building consent. The statement may be used to guide a development project, assess the impact of existing or future projects on the asset
Local planning authority authorisation to carry out specific work detailed in the corresponding submitted application, very often accompanied by conditions which must be shown to have been cleared before work can commence.
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Listing The designation by Historic England of buildings in the Statutory List of Buildings of
CONSERVATION GLOSSARY
Special Architectural or Historic Interest into three grades of significance, namely: I Grade I: buildings of exceptional interest I Grade II*: particularly important buildings of more than special interest I Grade II: buildings that are of special interest. Map regression A useful technique for identifying changes to a site and surroundings by comparing the present day map of a site to the earliest available maps. National Planning Policy Framework (NPPF) A government initiative providing guidance to local planning authorities and decisiontakers, both in drawing up plans and in making decisions about planning applications. Photogazetteer A graphically illustrated geographical index of the site, which may be needed for the conservation plan or simply used as a record and an aid to off-site discussions. Positive enhancement In addition to the removal of negative impacts, positive enhancement involves creating delight. Protected view The legal requirement within urban planning to preserve the view of a specific place or historic building from another location, such as views towards St Paul’s Cathedral in London. Reversibility Making repairs and changes to historic fabric in such a way that they can be undone at some time in the future.
Scheduled ancient monument A nationally important archaeological site selected by Historic England for inclusion on the Heritage List. Sensitivity This concept informs the technical approach to finding suitable design solutions for a building and relates directly to aspects of the historic fabric. Setting The surroundings of a listed building, generally defined by views but which can also include such considerations as flightpaths and below-ground archaeology. Significance An, often subjective, assessment of a site or building’s eligibility for planning/listed building consent. Spot listing A request for a building to be listed at short notice, often employed by objectors to a scheme as a tactic to delay the progress of a planning application. Statement of significance This considers factors of architectural/ aesthetic, historical, technical and social significance and is used by Historic England to determine a building’s eligibility for listing. World Heritage sites These are landmarks or areas which have been officially recognised by the United Nations Educational, Scientific and Cultural Organization (UNESCO), selected as important to the collective interests of humanity on the basis of their cultural, historical, scientific or other significance and legally protected by international treaties.
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RIBA Plan of Work 2013 glossary A number of new themes and subject matters have been included in the RIBA Plan of Work 2013. The following presents a glossary of all of the capitalised terms that are used throughout the RIBA Plan of Work 2013. Defining certain terms has been necessary to clarify the intent of a term, to provide additional insight into the purpose of certain terms and to ensure consistency in the interpretation of the RIBA Plan of Work 2013. ‘As-constructed’ Information Information produced at the end of a project to represent what has been constructed. This will comprise a mixture of ‘as-built’ information from specialist subcontractors and the ‘final construction issue’ from design team members. Clients may also wish to undertake ‘as-built’ surveys using new surveying technologies to bring a further degree of accuracy to this information. Building Contract The contract between the client and the contractor for the construction of the project. In some instances, the Building Contract may contain design duties for specialist subcontractors and/or design team members. On some projects, more than one Building Contract may be required; for example, one for shell and core works and another for furniture, fitting and equipment aspects.
its life cycle, from earliest conception to demolition’. Business Case The Business Case for a project is the rationale behind the initiation of a new building project. It may consist solely of a reasoned argument. It may contain supporting information, financial appraisals or other background information. It should also highlight initial considerations for the Project Outcomes. In summary, it is a combination of objective and subjective considerations. The Business Case might be prepared in relation to, for example, appraising a number of sites or in relation to assessing a refurbishment against a new build option. Change Control Procedures Procedures for controlling changes to the design and construction following the sign-off of the Stage 2 Concept Design and the Final Project Brief.
Building Information Modelling (BIM)
Common Standards
BIM is widely used as the acronym for ‘Building Information Modelling’, which is commonly defined (using the Construction Project Information Committee (CPIC) definition) as: ‘digital representation of physical and functional characteristics of a facility creating a shared knowledge resource for information about it and forming a reliable basis for decisions during
Publicly available standards frequently used to define project and design management processes in relation to the briefing, designing, constructing, maintaining, operating and use of a building. Communication Strategy The strategy that sets out when the project team will meet, how they will
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communicate effectively and the protocols for issuing information between the various parties, both informally and at Information Exchanges. Construction Programme The period in the Project Programme and the Building Contract for the construction of the project, commencing on the site mobilisation date and ending at Practical Completion. Construction Strategy A strategy that considers specific aspects of the design that may affect the buildability or logistics of constructing a project, or may affect health and safety aspects. The Construction Strategy comprises items such as cranage, site access and accommodation locations, reviews of the supply chain and sources of materials, and specific buildability items, such as the choice of frame (steel or concrete) or the installation of larger items of plant. On a smaller project, the strategy may be restricted to the location of site cabins and storage, and the ability to transport materials up an existing staircase. Contractor’s Proposals Proposals presented by a contractor to the client in response to a tender that includes the Employer’s Requirements. The Contractor’s Proposals may match the Employer’s Requirements, although certain aspects may be varied based on value engineered solutions and additional information may be submitted to clarify what is included in the tender. The Contractor’s Proposals form an integral component of the Building Contract documentation.
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Contractual Tree A diagram that clarifies the contractual relationship between the client and the parties undertaking the roles required on a project. Cost Information All of the project costs, including the cost estimate and life cycle costs where required. Design Programme A programme setting out the strategic dates in relation to the design process. It is aligned with the Project Programme but is strategic in its nature, due to the iterative nature of the design process, particularly in the early stages. Design Queries Queries relating to the design arising from the site, typically managed using a contractor’s in-house request for information (RFI) or technical query (TQ) process. Design Responsibility Matrix A matrix that sets out who is responsible for designing each aspect of the project and when. This document sets out the extent of any performance specified design. The Design Responsibility Matrix is created at a strategic level at Stage 1 and fine tuned in response to the Concept Design at the end of Stage 2 in order to ensure that there are no design responsibility ambiguities at Stages 3, 4 and 5. Employer’s Requirements Proposals prepared by design team members. The level of detail will depend on the stage at which the tender is issued to the contractor. The Employer’s Requirements may comprise a mixture of prescriptive elements and descriptive elements to allow the contractor a degree
RIBA PLAN OF WORK 2013 GLOSSARY
of flexibility in determining the Contractor’s Proposals. Feasibility Studies Studies undertaken on a given site to test the feasibility of the Initial Project Brief on a specific site or in a specific context and to consider how site-wide issues will be addressed. Feedback Feedback from the project team, including the end users, following completion of a building. Final Project Brief The Initial Project Brief amended so that it is aligned with the Concept Design and any briefing decisions made during Stage 2. (Both the Concept Design and Initial Project Brief are Information Exchanges at the end of Stage 2.) Handover Strategy The strategy for handing over a building, including the requirements for phased handovers, commissioning, training of staff or other factors crucial to the successful occupation of a building. On some projects, the Building Services Research and Information Association (BSRIA) Soft Landings process is used as the basis for formulating the strategy and undertaking a Post-occupancy Evaluation (www.bsria. co.uk/services/design/soft-landings/). Health and Safety Strategy The strategy covering all aspects of health and safety on the project, outlining legislative requirements as well as other project initiatives, including the Maintenance and Operational Strategy. Information Exchange The formal issue of information for review
and sign-off by the client at key stages of the project. The project team may also have additional formal Information Exchanges as well as the many informal exchanges that occur during the iterative design process. Initial Project Brief The brief prepared following discussions with the client to ascertain the Project Objectives, the client’s Business Case and, in certain instances, in response to site Feasibility Studies. Maintenance and Operational Strategy The strategy for the maintenance and operation of a building, including details of any specific plant required to replace components. Post-occupancy Evaluation Evaluation undertaken post occupancy to determine whether the Project Outcomes, both subjective and objective, set out in the Final Project Brief have been achieved. Practical Completion Practical Completion is a contractual term used in the Building Contract to signify the date on which a project is handed over to the client. The date triggers a number of contractual mechanisms. Project Budget The client’s budget for the project, which may include the construction cost as well as the cost of certain items required post completion and during the project’s operational use. Project Execution Plan The Project Execution Plan is produced in collaboration between the project lead and lead designer, with contributions from other designers and members of the project
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team. The Project Execution Plan sets out the processes and protocols to be used to develop the design. It is sometimes referred to as a project quality plan. Project Information Information, including models, documents, specifications, schedules and spreadsheets, issued between parties during each stage and in formal Information Exchanges at the end of each stage. Project Objectives The client’s key objectives as set out in the Initial Project Brief. The document includes, where appropriate, the employer’s Business Case, Sustainability Aspirations or other aspects that may influence the preparation of the brief and, in turn, the Concept Design stage. For example, Feasibility Studies may be required in order to test the Initial Project Brief against a given site, allowing certain high-level briefing issues to be considered before design work commences in earnest. Project Outcomes The desired outcomes for the project (for example, in the case of a hospital this might be a reduction in recovery times). The outcomes may include operational aspects and a mixture of subjective and objective criteria. Project Performance The performance of the project, determined using Feedback, including about the performance of the project team and the performance of the building against the desired Project Outcomes. Project Programme The overall period for the briefing, design, construction and post-completion activities of a project.
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Project Roles Table A table that sets out the roles required on a project as well as defining the stages during which those roles are required and the parties responsible for carrying out the roles. Project Strategies The strategies developed in parallel with the Concept Design to support the design and, in certain instances, to respond to the Final Project Brief as it is concluded. These strategies typically include: I I I I I I
acoustic strategy fire engineering strategy Maintenance and Operational Strategy Sustainability Strategy building control strategy Technology Strategy.
These strategies are usually prepared in outline at Stage 2 and in detail at Stage 3, with the recommendations absorbed into the Stage 4 outputs and Information Exchanges. The strategies are not typically used for construction purposes because they may contain recommendations or information that contradict the drawn information. The intention is that they should be transferred into the various models or drawn information. Quality Objectives The objectives that set out the quality aspects of a project. The objectives may comprise both subjective and objective aspects, although subjective aspects may be subject to a design quality indicator (DQI) benchmark review during the Feedback period. Research and Development Project-specific research and development responding to the Initial Project Brief or
RIBA PLAN OF WORK 2013 GLOSSARY
in response to the Concept Design as it is developed. Risk Assessment The Risk Assessment considers the various design and other risks on a project and how each risk will be managed and the party responsible for managing each risk. Schedule of Services A list of specific services and tasks to be undertaken by a party involved in the project which is incorporated into their professional services contract. Site Information Specific Project Information in the form of specialist surveys or reports relating to the project- or site-specific context. Strategic Brief
The Sustainability Strategy will be prepared in response to the Sustainability Aspirations and will include specific additional items, such as an energy plan and ecology plan and the design life of the building, as appropriate. Sustainability Strategy The strategy for delivering the Sustainability Aspirations. Technology Strategy The strategy established at the outset of a project that sets out technologies, including Building Information Modelling (BIM) and any supporting processes, and the specific software packages that each member of the project team will use. Any interoperability issues can then be addressed before the design phases commence.
The brief prepared to enable the Strategic Definition of the project. Strategic considerations might include considering different sites, whether to extend, refurbish or build new and the key Project Outcomes as well as initial considerations for the Project Programme and assembling the project team.
This strategy also considers how information is to be communicated (by email, file transfer protocol (FTP) site or using a managed third party common data environment) as well as the file formats in which information will be provided. The Project Execution Plan records agreements made.
Sustainability Aspirations
Work in Progress is ongoing design work that is issued between designers to facilitate the iterative coordination of each designer’s output. Work issued as Work in Progress is signed off by the internal design processes of each designer and is checked and coordinated by the lead designer.
The client’s aspirations for sustainability, which may include additional objectives, measures or specific levels of performance in relation to international standards, as well as details of specific demands in relation to operational or facilities management issues.
Work in Progress
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Index Note: page numbers in italics refer to figures. accessibility 58, 81–82 accreditation 4–5, 26, 105 aerial photography 23 archaeology 24–25 asbestos removal 115, 116 ‘As-constructed’ Information 122, 134, 151, 161 beneficial use 32, 67, 143, 157 BIM (Building Information Modelling) 53, 69–70, 161 briefing of construction workers 120 BS 7913: 2013 35, 81 Building Contract 54, 104–105, 161 Building Information Modelling (BIM) 53, 69–70, 161 building insurance 106 building life cycles 17, 148 Building Regulations approval 72 Building Regulations, Part L assessment 90 building services team 48, 81 (see also mechanical, electrical and plumbing (MEP) systems) buildings ‘at risk’ 29 buildings in use 17, 39 Burra Charter 2 Business Case 16, 24, 32, 161 cabling routes 119 CAMP (conservation area management plan) 33–34, 56, 157 Certificate of Immunity from Listing 28, 56 certificate of lawfulness 37 Change Control Procedures 119, 120, 161 changes affecting the building 146 cleaning the building fabric 148 cloud laser scan 53–54 Common Standards 161 Communication Strategy 161–163 Concept Design 61–75 condensation 52 conservation, definition 2
conservation architects 4–5, 54 conservation areas 19, 33–34, 49, 157 conservation area assessment 19, 33, 34, 56, 157 conservation area management plan (CAMP) 33–34, 56, 157 conservation deficit 26, 157 conservation glossary 157–159 conservation management plan 55, 57, 65, 68, 73, 84, 129 conservation plan 54–55, 57, 64–68, 84, 128–129 Conservation Register (RIBA) 5 conservation statement see heritage statement construction contract see Building Contract Construction Programme 162 Construction Strategy 73, 162 contingency sums 106 Contractor’s Proposals 162 Contractual Tree 162 Cost Information 68, 92, 162 cracking 143–144 cultural value 27, 47–48, 75, 157 curtilage buildings/structures 37, 55–56, 157 damp 144–145 dangerous materials see hazardous materials dangerous practices 102 dating building fabric 50 day works contracts 105 definitions 36 demolition 31 design and access statement 71, 89, 157 design coordination 80–81 Design Programme 162 Design Queries 162 design responsibility 105 Design Responsibility Matrix 162 design team 48 designated assets 4, 18, 25, 157 detailing 99, 101–102 Developed Design 77–92 disaster mitigation 81
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discoveries 117 documentation 56, 57 dry rot 145 drying out 130 dust jacking 144 ecclesiastical exemptions 33, 157 electrical cabling 119 electrical systems see mechanical, electrical and plumbing (MEP) systems embedded energy 50, 51 Employer’s Requirements 162–163 enabling development 26, 157 energy performance 50–51, 52 enhancement 57, 146, 158 ‘envelope of possibility’ 67 environmental impact assessment 71 environmental impact statement 85 exhibitions/displays 88 external heritage receptors 46 Feasibility Studies 46, 163 Feedback 38, 134, 163 Final Project Brief 74, 163 fire detection 119 fire engineering 81 fire hazards 102, 117 fire protection 118 glossaries 157–163 government buildings 151 grant aid 149 habitat protection 146–147, 148 Handover and Close Out 125–135 Handover Strategy 57, 73, 163 hazardous materials 58, 102, 116 health and safety materials 58, 102 site visits 29–30, 58, 146 Health and Safety Strategy 73, 163 HER (historic environment record) 18, 19, 84, 89, 158 heritage assessments 55 heritage assets (see also listed buildings) definition 18, 158 enhancement of 57 guidance and advice 34–35 identifying 18
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importance or significance of 25–26 need for designation 35 opportunities for sustaining and enhancing 30–31 Heritage Gateway 18, 19, 20, 47 heritage impact analysis 68, 71, 85–86 Heritage Partnership Agreements 132–133 heritage protection agreements 57, 73, 150, 158 heritage receptors 19–20, 21, 22, 46, 158 heritage statement 48, 57, 158 Historic England 158 historic environment record (HER) 18, 19, 84, 89, 158 hot work 102, 117, 118 ICOMOS (International Council on Monuments and Sites) 3, 26 impact assessments 68, 71 In Use stage 139–152 inclusive access 57, 81–82 Information Exchanges 163 at Stage 0 39 at Stage 1 58 at Stage 2 74 at Stage 3 92 at Stage 4 108 at Stage 5 122 at Stage 6 134 at Stage 7 151 Initial Project Brief 58, 68, 163 inspections 143, 146, 151 insurance 106 International Council on Monuments and Sites (ICOMOS) 3, 26 intrusive surveys 83, 87, 102–103 listed building consent for 55, 69, 71, 85 language (wording) 36, 86 latent defects 54, 83, 131 lead 101, 102 ‘least bad solution’ 86, 119 legislation 88 life cycle of building 17, 148 like-for-like repair and maintenance 37 lime mortar 100 listed building consents appeals 87–88 conditions 90–91, 98–99, 106–107, 121, 132 definition 158
INDEX
need for consent 36–37 at Stage 0 32 at Stage 1 55–56 at Stage 2 71–72 at Stage 3 89, 90–91 listed buildings Certificate of Immunity from Listing 28, 56 definition 158 demolition 31 eligibility for listing 27, 28 enriching the list 135–136 grading 4, 158–159 heritage protection agreements 73, 150, 158 identifying 19 listing description 55 locally listed 87 need for designation 35 scope of listing 37, 38 spot listing 24, 56, 159 local development framework/plan 34 local planning authority administrative boundaries 48–49 development plans and guides 88 pre-application discussions 32–33, 36, 72 local records 18, 19, 134 locally listed buildings 87 Maintenance and Operational Strategy 73, 163 maintenance programmes 65, 148, 151 map regression 23, 159 masterplan 68 materials availability 82–83 salvaged 83 samples 83, 86–87, 103 sourcing 99–100, 104 measured surveys 51, 53–54 mechanical, electrical and plumbing (MEP) systems 68, 81, 115, 119 method statements 103, 105 mock-ups 103 mortars 100–101 National Planning Policy Framework (NPPF) 88, 159 conservation areas 34 demolition of listed buildings 31 heritage impact analysis 85 NBS Create 82, 105 non-intrusive surveys 74, 84–85
opening up 69, 102–103 operation and maintenance (O&M) manuals 132 ordinary Portland cement (OPC) 101 performance specifications 103, 105 photogazetteer 66–67, 159 photographic records 104, 117, 130 places of worship 4 Planning (Listed Buildings and Conservation Areas) Act 1990 35 planning permission conditions 90–91, 98–99, 106–107, 121, 132 at Stage 2 71–72 at Stage 3 89, 90–91 plumbing see mechanical, electrical and plumbing (MEP) systems point cloud survey 53–54 policies for the management of change 67 positive enhancement 146, 159 Post-occupancy Evaluation 150, 163 Practical Completion 129, 163 pre-application discussions 32–33, 36, 72 preservation by record 133 procurement activities at Stage 0 31 at Stage 1 54 at Stage 2 70 at Stage 3 87 at Stage 4 104–106 at Stage 5 120 at Stage 6 129–131 at Stage 7 148–149 programme activities at Stage 1 54–55 at Stage 2 71 at Stage 3 87 at Stage 4 106–107 at Stage 5 120–121 at Stage 6 131 at Stage 7 149 Project Budget 49, 163 Project Execution Plan 73, 90, 108, 163–164 Project Information 133, 150, 164 Project Objectives 48, 164 Project Outcomes 48, 150, 164 Project Performance 150, 164 Project Programme 16, 31, 71, 164 project roles 54 Project Roles Table 164
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Project Strategies 164 project team 26, 48 protected species 146–147, 148 protected views 24, 159 protecting the building 58, 81, 104, 115–119, 129 provisional sums 106 public buildings 151 public engagement 88 Quality Objectives 46, 164 recording 104, 117, 121, 130–131, 133 research 50, 68–69 Research and Development 73, 89, 164–165 reversibility 86, 159 RIBA Conservation Register 5 Plan of Work 2013 8–11 glossary 161–163 Stage 0: Strategic Definition 13–40 Stage 1: Preparation and Brief 43–59 Stage 2: Concept Design 61–75 Stage 3: Developed Design 77–92 Stage 4: Technical Design 95–109 Stage 5: Construction 111–122 Stage 6: Handover and Close Out 125–135 Stage 7: In Use 139–152 rising damp 144–145 Risk Assessments 29–30, 58, 73, 165 salvage 131, 132 salvage and protection packages 103–104 salvage and protection plan 58, 73, 83–84 samples 83, 86–87, 103 scaffolding 118, 149 Schedule of Services 165 scheduled ancient monuments 18, 33, 159 section 106 agreements 91 security of the building contents 58 sensitivity 27–28, 75, 159 sensitivity analysis 67, 119 services see mechanical, electrical and plumbing (MEP) systems setting 24, 37, 159 signage 82 significance 27–28, 38, 159 (see also statement of significance) site induction process 120 Site Information 46, 165
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site visits 29–30, 58, 120, 121, 146 site waste management plan 92 skill set 3, 4–5 skills accreditation 120 soft landing 130 specialists 26, 48, 49–50, 66, 90, 105, 120 specification 99, 101–102, 103 spot listing 24, 56, 159 stakeholder engagement 88 statement of significance 47–48, 57, 67, 159 storing salvage 132 Strategic Brief 16, 39, 165 Strategic Definition 13–40 structural works 80, 115 subcontractors 106 supervision of works 113, 115, 120–121 surveys 49–50 (see also intrusive surveys) measured surveys 51, 53–54 at Stage 1 51, 53–54 at Stage 2 68–69, 74 sustainability 51, 58 Sustainability Aspirations 46, 165 Sustainability Checkpoints at Stage 3 90 at Stage 4 108 at Stage 5 122 at Stage 6 134 at Stage 7 151 Sustainability Strategy 74, 165 Technical Design 95–109 Technology Strategy 165 tender documents 103 thermal movement 144 third party consultations 73 U values 52, 74 undesignated assets 24, 28, 56 vapour barriers 74 variations to the contract 120 volunteer work 149 vulnerability analysis 67 way-finding 82 wildlife protection 146–147, 148 Work in Progress 165 work packages 103 World Heritage sites 49, 159