110 74
English Pages 200 [201] Year 2001
Approaching Urban Design The Design Process Edited by Marion Roberts and Clara Greed Introduction To Planning Series
ApproachingUrban Design
Series: Exploring Town Planning Serieseditor: Clara Greed Volume I Introducing Town Planning 2nd edition Volume II ImplementingTown Planning Volume III InvestigatingTown Planning Volume IV Introducing Urban Designs:Interventionsand Responses Volume V ApproachingUrban Design
Approaching Urban Design The Design Process EDITED BY MARION ROBERTS & CLARA GREED With contributionsby Bill Erickson, Tony Lloyd-Jones,Ali Madanipour,Chris Marsh, David Seex,Mike Theis and Tim Townshend
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Routledge Taylor & Francis Group
LONDON AND NEW YORK
First published 2001 by Pearson Education Limited Published 2013 by Routledge 2 Park Square, Milton Park, Abingdon, Oxon OXI4 4RN 52 Vanderbilt Avenue, New York, NY l 0017
Routledge is an imprint ofthe Taylor & Francis Group, an informa business Copyright © 2001, Taylor & Francis. All rights reserved. No part ofthis book may be reprinted or reproduced or utilised in any fom1 or by any electronic, mechanical, or oilier means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without pennission in writing from the publishers. Notices Knowledge and best practice in this field are constantly changing. As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary. Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein. ln using such intom1 ation or methods they should be mindful oftheir own safety and the satety of otl1ers, including parties for whom they have a professional responsibility. To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors, assume any liability for any injury and/or damage to persans or propetty as a matter of products li ab ility, negligence or otherwise, or from any use or operation of any meiliods, products, instructions, or ideas contained in the material herein. ISB N 13 : 978-0-582-30300-3 (pbk)
British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library. Set by 3 in Times and Melior
Contents
Contributors vii Acknowledgementsix Preface:Putting theory into practice xi
Block I
Understanding the city in terms of design
Unit 1
Design problems 3
Unit 2
Urban generators 8
Bill Erickson and Tony Lloyd-Jones Introduction Urban designas a decision-makingprocess Summary Marion Robertsand Tony Lloyd-Jones 'Movementsystems Natural features Developmentprocess Urban types Social and cultural meanings Summary
Unit 4 Making convivial places 39 Marion Roberts Introduction The pedestrianexperience Active frontages The importanceof mixed uses Scaleand grain Densities Spaceand time Determinateand indeterminatespaces Senseand stimulation Water, vegetationand art Summary Block III
Undertaking the design task
Unit 5
The design process 51
Unit 3 The 'armature' and 'fabric' as a model for understanding spatial organisation 21
Unit 6
Area analysis 57
Bill Erickson Introduction Definition of the armature Establishingdesigncriteria Gridiron plan Specifying the fabric Urban armatures Axes and movement Urban armaturesand the evolutionaryproject Conclusion:the armatureas an urbandesigntool
Marion Roberts Getting started Movementsystems Natural features Developmenteconomics Urban types Social processes Summary:opportunitiesand constraints Moving from analysisto an areaframework Summary
Block II
Approaching the design task
Tony Lloyd-Jones Understandingthe urban designprocess Artistic inspiration versusGeddesiananalysis Design as a problem-solvingactivity The urban designcycle and the importanceof types Design as a rational and experimentalprocess A framework for the urbandesignprocess Summary
vi
Contents
Unit 7 Design at the local scale 74 David Seex Introduction Site analysis Issuesinfluencing the arrangementsof buildings Designprocedure Summary
Unit 8
Casestudies 81
David Seexand Bill Erickson Introduction Cambourne Crown Street,Glasgow North Street,Clapham Kowloon Station Clerkenwell
Block IV Unit 9
The project in practice Urban designand development economics 105
Chris Marsh Introduction The structureof the property market Prime and secondarymarkets Developmentappraisaland financial viability The residualvaluationcalculation Mixed use, urban designand the property market Mixed use: the Clerkenwell casestudy Conclusion
Unit 10 Evaluationand user perspectives118 Clara Greedand Marion Roberts Introduction A framework for evaluation Clerkenwell Issuesin a userperspective Internationalcomparisons Summary
Unit 11
The contextfor urban designin practice 128
Tony Lloyd-Jones Organisations Clients and users User empowerment Clients' and users'requirements Local authority and planning requirements
Implementingurbandesign Public participation Summary
Unit 12 Urban designin the planning system 132
Tim Townshendand Ali Madanipour The questionof designcontrol What is involved in designcontrol? Planningdocumentsand design Central governmentguidance Documentsproducedby or for local authorities Preparinga designguide Village designstatements Designbriefs Design control in the United Statesand France Conclusion Summary
Block V
Information
Appendix 1: Getting started 143 Tony Lloyd-Jones Defining the context study area Basemapsand drawing scales
Appendix 2: Urban types 146 Bill Erickson and David Seex Urban grids Grid types Grid types and natural movement The size of blocks The streetin section Typical buildings and their requirements
Appendix 3: Planningstandards156 Tony Lloyd-Jones Public facilities and their catchmentareas Transportand sustainability Density standardsfor development Other useful planning standards
Appendix 4: Disability 163 Clara Greed
Glossary 165 Bibliography 173 Indexes 177
Contributors
Bill Erickson is a SeniorLecturerin Urban Design at the University of Westminster, London, and an architect. Clara Greed is Readerin the Faculty of the Built Environment, University of the West of England, Bristol, and is series editor for Introducing Town Planning. Tony Lloyd-Jones is a part-timeSeniorLecturerin Urban Design at the University of Westminster, London, and an advisor to the Department for InternationalDevelopment. Ali Madanipour is Readerin Urban Design and Director of PostgraduateResearchat the School of Architecture, Planning and Landscape,University of Newcastle-uponTyne.
Chris Marsh is Principal Lecturer in Surveying and Planning at the University of Westminster, London. Marion Roberts is Academic Subject Leader in Urban Design at the University of Westminster, London. David Seexis a SeniorLecturerin Urban Designat the University of Westminster,London, and a conservationist. Michael Theis is Director, Max Lock Centre and Archive at the University of Westminster,London. Tim Townshend is Lecturer and Degree ProgrammeDirector, MA Urban Design, at the School of Architecture, Planning and Landscape,University of Newcastle-uponTyne.
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Acknowledgements
First and foremostthe editors would like to thank the publishersfor their patienceand supportin producing this book. The University of Westminsterhas also provided some time for its production. We have some practitionersto thank for their willingness to let us use examplesof their work. Terry Farrell and Partners, Andy Karski of Tibbalds Monro and Urban Perspectiveshaveall beengenerousboth with time and material.David Lock of David Lock Associateskindly permitted us to use his masterplan for Ebbsfleet. Formerstudentsat the University of Westminsterhave also suppliedus with somefine examplesof their work and we must thank them for their diligence in producing it and for their willingness to let us exposeit to public view. We are especially grateful to Caroline Lwin, JaneFowles, Mike Martin and Martin Evans in
this regard.Hugh Barton of the University of West of England has kindly allowed us to draw on his standardsfor catchmentareas.Graham Shane of Columbia University in New York provided us with a redrawn diagram of his now famous analysis of the 'great estates'in London. Finally, may we take this opportunity to state thatall of the studentprojectsillustrated are hypotheticaland have no relation to any real proposals,pastor present. Every effort has been made to trace the owners of copyright material; however, in a few casesthis may have beenimpossibleand we take this opportunity to offer our apologies to any copyright holders whose rights we may haveunwittingly infringed.
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Preface: Putting theory into practice
The purposeof this book is to provide a primer that will enablethe application of sensitive designprinciples to urban form. The wider conceptual basis of urban designwas discussedin the precedingcompanion volume, Introducing Urban Design: Interventions and Responses(Greed and Roberts 1998), in which key principles,considerationsand conceptswere introduced.In this volume we will seekto show how these might be applied and implementedwithin a range of real-world settings. Manuals providing guidancefor studentsof urban designhavebeenrelatively sparseuntil recently.While there have been many good examplesof designguidanceproducedby local authoritiesfor developersand planners(seeCarmona1998 for a discussion),students have had less choice. ResponsiveEnvironments,producedin 1985 by Alcock, Bentley, McGlynn, Murrain andSmith, a teambasedat Oxford BrookesUniversity, proved to be a ground-breakingtext. It provided help for studentswho were completelynew to designtasks by explaining principles and techniques,while at the same time promoting the team's view of a desirable approachto urban design. The strength and usefulness of Responsive Environmentswas demonstratedby its progressinto a new edition in 1996 and its pre-eminencein the field (Bentley 1996). By the mid-1990s urban design had continued to flourish as a field of activity and as an academic discipline (Urban Design Group 1998). Many more higher education institutions had established postgraduatecoursesin urban design, or with urban designas a specialisationfor other postgraduate courses in subjects such as architecture, landscape architectureand regeneration.Some planning courses
had madeurban designtheir 'specialist' areaof study under the Royal Town Planning Institute's accreditation scheme. Within the professions, urban design practitionerswere working for public authorities and private interests,at both home and abroad. The field was in a stateof flux and it seemedappropriate to producean alternativestudenttext thatwould reflect a different design approach and another temporal and geographic context. Responsive Environmentshad been based on the authors' own expertise which had been geographically based in 'middle England'. Urban design, by the mid-1990s, was being practisedin a variety of contextsin Britain and overseaswhich were throwing up different setsof problems and issues. This book has been produced mainly by a team from the University of Westminster, with contributions from academics based at the University of Newcastle upon Tyne and within the overall series editorship of Clara Greed at the University of West of England. At the University of Westminster students are coming to grips with the problemsof complex inner city sites in a highly pressurised developmentcontext, and it seemstimely to sharethis metropolitanexperience,since the approach that evolvesthroughtackling thesedesigntaskscan be appliedequally well to lesspressurisedand rural settlements.In addition,aslevelsof expertiseandknowledge grow, it is also importantto setout the theoreticalbasis for a designapproach,sincesuchtheoreticalprinciples would and shouldbe subjectto constantre-assessment and revision. This manual sets out to do this, by providing a discursivefirst part which discussesthe origins of the authors'approach,beforeproceedingto a second part which providesguidanceon 'how to do it' .
xii
Preface:Putting theory into practice Since starting on this book other agencieshave commissioneddesignmanuals thatare intendedto provide national standardsof guidancefor practitioners. Urban Initiatives, in an extensive study for the Department of Environment, Transport and the Regions,hasproduceda guide for plannersand developers(DETR and CABE 2000). This, togetherwith an Urban Design Compendium, commissionedby the regeneration agency, English Partnershipsand the Housing Corporation and produced by LlewelynDavies will provide good, well-illustratedguidancefor competentpractitioners.This volume, by contrast,is directedat studentsand is basedon the authors'extensive experienceof teachingat postgraduateand undergraduate levels. The distinguishing features of this volume are as follows: • it is directed at undergraduatesin planning, architecture, landscapearchitecture and postgraduates from 'non-design'disciplines; • it provides 'hands-on'guidancein tackling a range of urban designtasks; • it explains the theoreticalbasis for an approachto designand relatesit to 'hands-on'guidance; • it provides backgroundinformation and a glossary of 'jargon' terms.
Contents The book is intendedas a designmanual.It is divided into five blocks: background; an explanation of approaches;carrying out the urban designproject; the project in practice; and information. The first two blocks are more discursive, the third block diagrammatic, the fourth discursiveand finally the last block provides a seriesof notes, guidelines and references. Each block is relatedto the other, but it is anticipated that readersmay wish to 'dip' into and out of different blocks and units as they use the book. The first block, Understandingthe City in Terms of Design,setsthe scene.Thereare obviously many ways in which cities canbe understood,for examplein terms of sociology, economics,as cultural artefacts,as the products of planning policies; the list is long. This block setsout somebasicideasaboutdesignand urban design which form the backgroundto our suggested approachto what urban design is as an intervention into towns and cities (Figure P.l). Towns and cities can and do develop without the explicit attention of professionalswho style themselvesurban designers, but this is not to say that towns and cities are not designed.Furthermore,in order for urban designersto
make beneficial proposals,it is important for them to understandthe forces or factors that influence city developmentin designterms. Somebrief introduction is also madeto urban designas a process. In Block II the authors'approachto undertakingan urbandesignprojectin a practicalhands-onsenseis set out. In Unit 3, the significanceof movementsystems, public and private space,and scale are explained in terms of their importancefor analysisand design.The conceptof the armatureis set out, both as a tool for analysis and as a structuring device with which to approachan urban design task. Unit 4 recountswhat are now rapidly becomingmainstreamideasfor creating convivial spacesat a local scaleand explainstheir origins. Block III providespracticaladviceon how to tackle a project. Readersshould use the information part of the book as a supplementto the advice given here. Design is a processthat is often shroudedin mystique by its practitioners.Unit 5 clears up some misunderstandingsby offering alternative descriptionsof the design processand a discussionof the processitself. Unit 6 dealswith making an areaanalysisand deriving an urbandesignframeworkfrom it, using an inner city areaand site in London. An inner city areaand site has beenchosenbecauseits complexity throws up most of the urban issues that students may have to grapple with. Moving from areaappraisalto the problemsof a specific site demandsa different level of analysisand some understandingof buildings and their requirements; Unit 7 dealswith theseissues.Unit 8 provides an explanationof how to move from analysisto concepts and a rationale, and illustrates this with five worked examples.Casestudiesfrom urban and rural Britain and Hong Kong are explained to inspire studentswith a variety of possibilitiesand to demonstrate how urban design principles and methods may be applied to differing situationsand tasks. Block IV providesanotherlevel of iteration, or repetition, to the design processin making the relation betweenprojectsand practice 'in the real world' more explicit. In Unit 9, basic concepts of development economicsare explainedand applied to the inner city worked example.The argumentfor this unit is that in real life, designershave to engagewith development economicsand producepositive proposalswithin the constraintsof finance and profitability. Unit 10 offers someideasfor evaluatingurbandesignproposalsfrom the perspectiveof the 'user',i.e. peoplewho might be affectedby the proposals.Urban designis an iterative, collective processand it is hoped that reading these units will encouragereadersto return to and refine their proposalsafter the first draft. Unit 11 providesa further
Preface:Putting theory into practice (a)
(b) Informal 'hedgerow' planting softens distinction between urban and rural \
Informal planting softens space Building front overlooking public space improves security
Narrow 'garden' area reflects domestic planting found elsewhere in Tenterden
Back GAROEN
BACK
PRIVATE OPEN SPACE)
FRONT
FRONT
{PUBLIC OPEN SPACE
SHARED SURFACE ACCESS ROAD OR PRIVATE DRIVE
Figure P.l Urban designoperatesat a rangeof scalesfrom masterpiansfor new regional centresto designguidanceat the intimate scale of the back garden. Both of the examplesshown here come from the same county in England. (a) Masterplanof Ebbsfleet,Kent (David Lock Associatesfor Whitecliff Properties).(b) Design guidancefor Tenterden,Kent (Tibbalds Monro Ltd).
xiii
xiv
Preface:Putting theory into practice explanation of the ways in which urban design is carriedout in practice:who it is carriedout for andwhy. The final unit makes the links betweenurban design andplanningpracticein an Englishandan international context.Planningauthoritiesare making greateruseof design guidelines and urban design studies and it is likely that this areaof work will grow in the future. Block V sets out some information and 'tools' for assisting readers in tackling design projects. In Appendix 1 there is advice on getting startedand on practical issuessuchas which scaleto use.Appendix 2 gives advice on what are literally the 'building blocks' of urban design: grid patterns,block sizes, street sections, and the requirementsof different building types. Appendix 3 tacklesthe practicalissuesof spatialplanning at a larger scale and provides information on catchment areas for facilities, the relationships betweennumbersof facilities and density,the relationship between transport systems and density, and a guide to the measurementof density itself. In providing this information and advice, principles of sustainability have been incorporated.Attitudes to what are deemedto be acceptableliving conditions vary internationally and someinternationalcomparisonsare sup-
plied. Appendix 4 acknowledgesthat over the past 10 years there has been an increasedrecognition of the needsof thosewhosemovementsuffers temporaryor permanentimpairment- not only the physically disabled but also people pushing prams, elderly people, and those suffering from temporary injuries. This appendixdirects the readerto somerelevantliterature for guidance. Finally, one of the key problems urban designers face in teachingand in communicatingwith the public is that of professionaljargon. It is difficult to avoid this, for as knowledgeand understandingevolve, it is inevitable that new terms and expressionsare coined. The glossary provides explanationsfor key terms in urban design with some forays into relevant areasof planningand architecture.Limits havehadto be placed on its extent,but we hopethat readerswill refer to it as they read the book. There is no formal conclusionto this book as it is a practical manual rather than an overview. Working on it has been an exhaustingbut salutaryprocess;we hopethat it will be of use. Clara Greedand Marion Roberts Bristol and London, 2001
BLOCK I UNDERSTANDING THE CITY IN TERMS OF DESIGN
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Unit 1 Design problems
Bill Erickson and TonyLloyd-Jones
Introduction Urban design, like any other design process,involves method as well as inspiration. This book investigates the challengeof the designproblem; where to start and how to proceed. This unit will explain design as a process and how that process can be applied to an urban situation. In simple terms, design attempts to make the future better than the present(Figure l.1). This involves planned changein the material world. The design process seems easy looking backwards. When a projected design is implemented one can
existing condition
Is this good or" bad?
time
proposed change
Desig n stag e
..ow
Would this be better or worse?
future
Figure 1.1 Design process:outline.
Implementatio
n
ACTION
usually look back and evaluateif it has been successful, whetherit hasimprovedthings or not. If all designers had the benefit of hindsightsurely the world would be a better place. The challenge and skill of good design requiresnot only that one envisagesthe future but also that one imagineschangeand its likely impact. Consider the design of a car, for example. Designersstart by askingwhat makesa good car. Then they look at what is already known: the existing car. The designtask can be defined quite accurately- perhapsthe car needsto be cleaner,faster, safer, quieter, etc. As each aspectof the car is worked on it can be assessed againsttheseparticularcriteria. Someaspects may be more difficult to improve- the car may needto be more stylish or fashionable- but this too can be testedby using modelsand testingconsumerreactions. Every single detail of the car is consideredand once the new car is designed,testedand perfectedit can be put into production.The designtask is over. The first task is to identify the existing condition ('where we are'), and evaluateif it could be improved (,where we want to be'). Thesedesignobjectivesmay be quite general butwill guide the process.To help, a detailedanalysisof the existingconditionis undertaken from which it is possible to list opportunitieswhere improvements could be made. Analysis may also enablebenchmarksto be set, againstwhich improvementscan be measured.Takentogetherthesegive a set of designcriteria which identify need.This first stageis sometimesknown as the designbrief; it setsthe agenda for changeand definesthe designproblem. Designersare always asking questions.The second step is to posit new design scenarios,to 'try on' new ideasand 'seeif they fit'. This involves the generation
Design problems
• It is cyclic and open-ended;there is always room for improvement. • Proposingdesignsolutionsleadsto a redefinition of the designproblem. • Becausecriteria are often conflicting there is no right or wrong solution but rathersolutions that are more or less for the better. • Design requiresus to be inventive in creating new scenariosbut rational in testing them against criteria. • The analysisphaseis an integral part of the des.ign process.To get the right answerswe need to pose the right questions. Some design tasks are simple and anyone can undertakethem, e.g. deciding what clothes to wear on a cold day. In an age of technology, design is an important activity. Specialistdesignersdevelop skills
objective s
analysis
brie f
existin g
design criteri a
design scenarios
design solution
proposals
test s
design solutio n
of a rangeof new 'what if' ideas.Each new scenariois tested against the design criteria. Those scenarios which appearto satisfy thesecriteria are retainedwhile others are discarded.Thus an important part of the design processis the generationof new ideas; this is the creative part of the process.Frequently,however, the designcriteria are numerousand at times conflicting. For instance,in the exampleof the car, the criteria of faster, safer and cheapermay be difficult to reconcile. This leadsto a processwheredesignscenariosare combinedand developedor improved to meetone and then anotherof the various criteria. Sometimesseveral solutions may emerge and in this later stage the importance of the testing phase becomescrucial in selectingwhich ideasare the best. Seenlike this, designis not a simple linear process but an open-endedprocesswherethere is always room to introduce innovation. The design solution emerges from this iterative processnormally when most of the criteria have beenmet to somedegree.The designsolution can be seenas the synthesisof severalscenarios and forms the basisfor action. Each designsolution is unique and one of many that could possibly fit the problem. The basic diagramof the design processcan be redrawnto include this cyclic process(Figure 1.2). In the designprocessthe designproblem itself is constantly revisited and refined. The activity of exploring design solutions requires a constant re-evaluationof the design criteria and design objectives. Where the design problem involves numerousand perhapsconflicting criteria, design testing can be extremelyuseful in determining the relative importanceof various criteria and may even exposenew ones. This highlights several important aspects of the designprocess:
ACTION
new condition
implementatio n
4
Figure 1.2 Design process:stages.
in a particular field which enable them to become experts. For example, a computer designer needs to know a lot about electronicsand a little about plastic boxes,while a musical composerneedsto know about soundand instruments.We associatethesepeoplewith the things they designand group them into distinct professions.Associatedwith eachprofessionis a body of specialist knowledge and a variety of methodologies that have been found useful in particular designproblems. In the built environment the range of professional designerstends to be distinguished by the scale at which they work (Figure 1.3). At one end of the scale we have objects smaller than people such as
Introduction
Political unit
Individual
Family building user
Local groups: institutions
Local authority
Government
Built form
Room
Building
Building complex
City
Metropolitan region
Urban space
Courtyard
Street or square
Quarter
City
Metropolitan region
Urban design
Furniture and product design
Design activity
Planning regional infrastructure
Architecture
Physical planning
Interior design Landscape architecture
Smaller
Figure 1.3
Scale at which various design activities take place in the built environment
Larger
Scale of design activity in the built environment.
furniture, consumer products and clothes. In the mid range are buildings and spaces within which we can move around. At the large scale, cities and urban regions also involve spatial planning. We can see that urban design is undertaken within the context of other design activities operating at differing scales and in differing time frames. Cities are difficult to design. Rather than being replaced with a new model, existing ones are adapted. Cities are complex and constantly changing, and the simple question 'what makes a good city?' is always difficult to answer. Most important of all, a city can never be designed in every detail. This is not to say that the urban environment is not designed in detail; it
certainly is, e.g. each building is designed in turn. Most features of the urban environment are designed by someone. Even the location of lamp-posts and the positioning of natural features such as trees is determined by a design process. Many of these decisions are made within a loose framework by people who may know only a little about what is going on in the rest of the city. Many design decisions lie beyond the scope of the urban design project, and may be made years later by various architects, builders, planners or developers and in a variety of ways. It is clear that for urban designers not only is the substance of the design process, i.e. the fabric of the city, complex, but so too is the professional context in which design takes place. We will
5
6
Design problems return to the substanceof urban design in later units where we will investigatemethodsfor both analysis and design. However, first we will introduce the professionalcontextin which urban designers operate.
Urban designas a decision-makingprocess With a few notable exceptions,cities are seldom the work of a single individual designerbut are the product of a myriad of particulardecisionsaboutthe urban environment,taken individually or collectively and at a variety of scales.While this book focuseson the professionaldiscipline of urbandesign,as a processit can involve all types of people. Local people making a decisionon the location of a school; engineersdesigning an urban motorway or architectsa regional shopping mall; plannerssettingout urbandesign guidelines for a suburbanconservationarea; landscapedesigners planning a small town park - all are in somesenseor anotherengagingin urban design since all contribute to the developingurban form of the city. Very different sets of actors and decision-makingprocessesare, however,involved in eachcase. Since it involves decisionsabout the allocation of resourcesto shape the physical environment, urban designis inevitably an economicand political, as well as an aestheticand functional process.In this book, it is assumedthat decision-makingtakesplace in a contemporary planning and developmentcontext, within which urban design,as a recogniseddiscipline, has an important and centralrole. As we have seen, we are concernedwith a rangeof scales,from the city district to the individual site or local urbanelement.In certain instances,we may be looking at the form of the city as a whole, or even urban form and activity at the larger metropolitanscale. Within the planningsystemas it is in the UK and in most other countries, however, there is little opportunity for exploring urban design and spatial planning at the wider scale since the means of implementing policy at this level does not currently exist. Our concerns, therefore, will focus mainly on urban design interventionswithin an existing urban context, simply becausethat is where most urban designeffort is currently directed. However, the design approachof this book is equally applicableto the designof new settlements or to new extensions to existing towns and cities, as in the more economicallydynamic and rapidly urbanising parts of the world. Urban design can take place in a variety of developmentcontexts- public, private and communitycontexts as well as contexts that combine all these
elements. Urban designers can find themselves employedby anyoneof a numberof 'stakeholders'partieswith a direct interestin a particularsite, street, neighbourhoodor larger urban area.A client could be a local authority, a regenerationagency, a housing association,a private developer or landowner, or a community organisation. In working for one stakeholder, an urban designer will neverthelessneed to take accountof the outlook of otherswith an interestin a particulardevelopmentissue.In Unit 11, we explore these matters, and their influence on how and where urban designis usedin the contemporarydevelopment context, in more detail. This book offers two tools or approachesfor making sense of urban design within this complex decision-makingprocess.Unit 3 introducesthe idea of an urban armatureas a frameworkor primary structuring device for the city. The armaturesits within our method framework, as a basis for establishinglarger urbandesignstrategiessinceour stressis on the city as a connectedsystemof movementspaces.Unit 5 introduces the notion of a methodframework for urban design, drawing on the idea of design as a cyclic process.However,it is also possibleto follow the same urban designprocessand adopta strategythat is based on prioritising other factors: land use, landscapeor other physical, economic,political, aesthetic,cultural or social factors. In other words, the framework is quite generalin its application and can encompassa very wide rangeof urban designapproaches.
Summary The main points of this unit can be summarisedas follows: • Urban design, like any other design process,combines rational method with inspiration. Design involves planned change in the real world and involves envisagingthe future and the likely impact of change. The starting point is an analysis of the existing situation and the design 'problem'. In the design processwe tryout ideasto seeif they fit the problem -a processthat is cyclic and open-ended.As there are many criteria for a successfulsolution, and some of thesemay conflict - no perfectsolutionis possible. Urban designis taken within the contextof other design activities operating at different scales and different time frames. • We can never design the city in every detail and both the fabric of the city and its decision-making
Summary
context are complicated.Urban designis an econopmentcontexts- public, private and community, omic and political, as well as an aestheticand funcand in contextsthat combineall of theseelements. tional process,often involving a shifting cast of • Urban designerscan find themselvesemployedby anyoneof a numberof 'stakeholders'and needing players. • We will refer mainly to the UK planning and to addressthe interestsof those who are not their developmentcontext although the principles outemployers. lined in this book apply across a range of urban • Our main tools for dealing with the complexity of decision-making in urban design are a method development contexts including areas of rapid framework and the conceptof the urban armature urbanisation. • Urban design can take place in a variety of deve1(structure).
7
Unit 2 Urban generators
Marion Robertsand Tony Lloyd-Jones
This unit discussesthe principal factors that, we would argue, shape the form and substanceof towns and cities. We havecalled these 'urbangenerators'.
Movementsystems When a tourist goes to a new town the first item they needin orderto start explorationis the streetmap. The map of a city providesthe basic information about that city and illustratesthe movementsystemwhich defines the 'structure'of that place, i.e. how the whole relates to the parts.
Movementsystemsand urban development Whereasnowadaysmovementcan be undertakenby a numberof meansor modesof transport,up until a century ago walking or being carried or pulled by a horse provided the only options. Most cities still have the street network as their primary arteriesof movement, or hybrids of them as in the urban motorway.The technologies of movementsystemsinspire different types of urbanform. For example,the winding back alleys of medievaltowns are really only passableon foot or with one other animal such as a horse or a mule. By contrast, the ornate central boulevardsof Paris are best appreciatedat a smarttrot behind a horseand carriage. Finally, cities such as Houston in the USA are best appreciatedwhen approachedfrom an urban motorway; here the glittering sides of the tower blocks almostseemto draw the car in at an exhilaratingspeed. As can be seenfrom each of theseexamples,each
mode of transport has inspired a different scale of urban form: • three- to four-storey height medieval lane (pedestrian, horseand cart); • seven- or eight-storey Parisian apartment block (pedestrians,carriages); • multi-storey American skyscraper(motor car). Interestinglythe first two examplesinvolve the buildings being closely packedtogetherso that a continuous fac;:ade appearsto be formed as the traveller moves through them. In the case of the skyscraper,the car moves so fast that it is possiblefor the skyscrapersto be spreadout and yet still give the impressionof a continuous wall of building (Figure 2.1). Another important aspectto notice is the loss of transferability from one type of movementsystemto another.It would be impossibleto run a two-way highway with modern parking standardsdown a medieval lane. Similarly, althoughParisianboulevardsare wide, they are still not wide enough to accommodatean urban motorway. Conversely,travelling on foot by the side of a busy urban road is a distressingand uncomfortable experienceunlessthereis screeningby treesor someothertype of landscapingdevice.Hencenot only are movementsystemsimportantto the definition of an urban area,but the scaleand type of movementsystem also has an influenceon the type of urbanform and the pedestrian'sexperienceof it. Many ancient urban settlements evolved from movementsystemsforming a crossroador from two systemscrossingeach other. In the era of the fortified city, the city walls definedthe limits of the urbanstructure, i.e. the extent of the city itself. Nowadays the
Movementsystems
Figure 2.1 A Frankfurt street(Bill Erickson).
movement system performs this function in a more ambiguous manner. Roads and railways can form barriers to movementthat are as powerful as a wall. Tamed, they can also form a 'seam' which joins one part of the city to anotherso that the districts or neigh-
bourhoodsare formed around the movementsystem. Cities that havegrown overa longerperiodof time have a less clearly articulatedstructure,but neverthelessthe systemsof movementhavea clearand closerelation to the districts, partsof the centreand sub-centres.
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Urban generators Types of movementsystems The numberof patternsof movementsystemsin urban areasis potentially large, but threemajor types tend to dominate.The first is the radial system,which tendsto developas routesare madefrom a centrethat is formed by a crossingpoint. The rbadswhich divergefrom this central point are often referred to as arterial routes the analogy being with a body or a tree. In London some arterial routes date back to the period of the Roman occupationof Britain and, as Mike Hebbert (1998) notes, still form important mixed-usecorridors to the centre. The second systemconsists of concentric roads. Many ring roadshave historical origins, such as those that originate from when the city walls were torn down, as happenedmost famously in Vienna with the developmentof the Ringstrasseat the end of the nineteenthcentury. TheRingstrassewas createdas a broad streetwith many monumentalbuildings along it when the city walls were demolishedin the nineteenthcentury. Nowadays the undesirability of forcing heavy traffic and major new roads through existing city centres has led to the constructionof ring roads around many urbancentres(Figure 2.2a). Paris forms an interestingexampleof this, wherethe Peripherique,formed at the boundary of the ancient arondissementsor boroughsin Paris, forms a sharpedge with the poorer suburbs or banlieues excluded beyond it. Gridded systemshave been particularly important as organis(a)
ation patternsfor cities in both the easternand western hemispheres(Figure 2.2b). Further information about grids is given in Appendix 2.
Movementsystemsand urban regeneration Increasingly,movementroutesarebeingusedto encourageurbandevelopment.In the 1930sthe building of the Metropolitanline of the Undergroundhelpedto spawn that whole north-westsectorof London.Whilst building on virgin territory is currently moreconstrainedin most Europeancountries, in the USA Garreau (1991) has noted the developmentof new peripheralsettlements, which he calls 'edge cities' around the junctions of major highwaysjust outsideexistingcities. These'edge cities' tend to consist of housing estatesfor middleincomefamilies, shoppingmalls andbusinessparks,all connectedby roadsin a mannerin which one bearsno formal relationto the other. In Europe the hope is that the insertion of new transport systemswithin urban areaswill lead to the regenerationof thosedesolateareaseither in the inner city or at its periphery, boosting residential property prices and increasingaccessto employment.Whether regenerationcan always be achievedby such means has still not beenprovenand more researchneedsto be carriedout. Cowan (1997) arguesthat neighbourhoods have to be well-connectedby infrastructure such as transport and through physical connectionssuch as (b)
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Figure 2.2 (a) Road network of London; (b) the grid patternof Raleigh, North Carolina (DonnaTurnbull).
Movementsystems streets and pedestrian routes to achieve successful regeneration. The retrofitting of new transport and movement systems can cause huge problems in design terms. Cuttings and underpasses are often both ugly and dangerousand the insertionof a new fast road canliterally 'cut' away the urban fabric like a gash in skin. Even benign measuressuch as pedestrianisingpreviously trafficked areas can produce unexpectedeffects. For example, rents in South Molton Street, off London's fashionable Bond Street, rose fourfold once it was pedestrianised,driving all but the most specialisedand high-classshopsout. The analogy betweenmovement systemsand the arteriesof a body is both useful and descriptive.It has been amplified in the past few decadesbecause,as buildings have become more complicated and more dependenton services to them, such as water, gas, electricity, telephonewires and, for specialisedfunctions, fibre optic cables,theseserviceshave tendedto follow the roads.This meansthat the 'lifeblood' of the urban system (people, heat, light, water) is literally travelling through these movementsystems.Without movement,cities would not exist. Growth and change are dependentupon movementsystems,but as with the body, controlling the effects of changeand the ability to conductmajor surgery sensitivelyare still not fully within our capabilities.
Sustainability
Figure 2.3 Grenoble: tramway system retro-fitted into the heartof the city (PeterJones).
ForceReport- Towardsan Urban Renaissance(Urban TaskForce 1999). Planningpolicy guidelineshavealso beenrevisedand producedto reduceincentivesfor car useby curbingthe growth of out-of-towndevelopments and promoting existing town centres. Continental Europeprovidesmore radicalinstancesof reducinguse of the private motor car and promoting attractive urban designsolutions,as for examplein the introductionof a light rail systeminto the city of Strasbourgin France andin the Dutch planningsystemwith its threelevels of permissibledevelopmentwhich are relatedto transport nodes(seealso Figure 2.3). As has been hinted at above, sustainabledevelopment raisesissuesof density anduse,in that the higher densities of nineteenth- and early twentieth-century settlementsare proposed,as well as a greatermixing of uses (Coupland 1996). Urban designershave long beenarguingfor theseprinciplesto be includedas part of planning practice. In this design manual, it will be assumedthat the principle of reducing car use is a desirable objective that should run through urban design interventions at all scalesof development.In some casesthis may mean contestingexisting planning standardsand norms, e.g. in terms of parking provision. This places a challengeupon designersto think through standardsfor themselvesand to be able to justify any guidelines which they produce. Appendix 3 of this book provides further information on the connectionsbetweendensity, urban form and transportsystems.
Movement is intimately connectedto the 'environmental sustainability' of particular urban structures. Over the past two decadesconcern has been rising about the use of the car and its harmful effect on the environment. In North America, the New American Urbanismmovement,spearheaded by PeterCalthorpe, Andres Duany and Elizabeth Plater Zyberg (DPZ) (Calthorpe 1993; Murrain 1993; Katz 1994), has proposednew typesof urbanstructurefor new settlements and for infills to existing settlementswhich are based aroundmasspublic transportsystems. In WesternEurope,calls havebeenmadeto returnto the traditional form of the Europeancity in an attempt to curb andreducethe needfor the motor car. Currently thereis muchactivity in exploringthis issueat all levels of government.In Britain, researchand guidelineshave beendrawn up for the planningof sustainablenew set- Summary tlements(Barton et al. 1995; Aldous 1992) and for providing housing at higher densities (Llewelyn Davies • Different types of urban form have been supported by technologicalchangesin movementsystems(i.e. 1998).A comprehensiveapproachto achievingsustainfrom horse-drawncarriagesto cars). able urban developmentwas set out in the Urban Task
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Urban generators naturalfeaturesthat form an integral part of their identity, such as Table Mountain in Cape Town, South Africa. The protection of these natural features from inappropriate developmentthrough the evolution of designstrategiesis becomingincreasinglyimportant. The transformationof natural featuresinto a used landscapeoften forms a key part of a town or city's evolution and providesan explanationfor the development of a particulartype of urban structure.In Berlin, for example, the one-time royal hunting park, the Tiergarten, forms an important green area within its urban core. The canalsin Amsterdamand Venice are themselvesintegral to the cities, which havedeveloped Natural features in conjunction with them. At times, the influence of Environmentalsustainability,as a concept,is difficult natural features may be hidden and only legible to to define. It is not only about reducing pollution, but those with a deepknowledgeof the city. In a particualso incorporatesthe idea of conservingand maintain- larly intriguing diagram, the urban designerGraham ing the biodiversity of specieson the planet. This is of Shane has shown how the 'great estates' built by importance to the generationof urban forms within wealthy landowners in eighteenth-centuryLondon cities and for the urban structureof a city as a whole. were built on the more solid, higher ground abovethe It is a commonplaceto note that cities have often tributaries of the River Fleet which flowed into the formed aroundnatural features:around ports and har- Thames(Figure 2.4). The tributaries of the Fleet were bours, at river crossings,or in the natural 'bowl' of a eventually built over, with a more haphazardform of range of hills. In addition, many cities incorporate development. • Movement systems have been associated with urban developmenthistorically and are now being usedas a tool for urban regeneration. • Major patternsof movementsystemsare radial or arterial routes,ring roadsand grids. • Movementsystemsare important for issuesof sustainability and regeneration. • Infrastructure systems, such as telephone lines, water and gas are often routed under roads and henceare closely connectedto movementsystems.
Figure 2.4 Field diagram of London (drawn by GrahamShane).
Developmentprocess Urban designers then, have to pay attention to natural featuresfor their generativeproperties.This is not to imply that natural features are awkward elementsto be built round or bulldozed; green vegetation, indigenous flora and fauna, water, trees and clean air all have restorativeand structural properties that can and should play an important role in design proposals. Methods for the incorporation of natural features into urban design solutions merit an entire volume on its own. Throughoutthis manual, suggestions will be made for how natural featuresmight be incorporated in the light of the examples used. Referencecan also be madeto Thompson(1998). A problem for designersis that green landscaped featuresdo not of themselvesgeneratevalue in terms of return to the landowner.Indeedthey often may carry a considerablecostin termsof maintenance.In a sense, urban developmentand the natural world can sometimes seemat loggerheads:whereland valuesare high, then there is pressureto build on all available space. This leads on to the next generator,which is development economics.
which takes place almost without human agency. Kostof (1991) remindsus that all developmentshavein some sensebeen planned: whether it be the sinuous curvesof a quiet road in HampsteadGardenSuburbin London, the formal layout of the Rue de Rivoli in Paris or afavela (squattersettlement)in Sao Paulo, eachof thesesettlementshas some set of rules, of agreements coveringtheir shape,orientationto the sun, or relationship to their neighboursor to the road, howeversimple or rudimentarysucharrangementsmight be. It is perhaps in the cities of rapidly developing countriesthat we see the most stark exposition of the relationshipsbetweenland values,political control and urban form. In the centre of cities such as Sao Paulo and Mexico City where land prices are high, tall skyscrapersdominatethe horizon. Becausethesebuildings are owned and usedby the most wealthy of its inhabitants, the semi-privatespacesof thesebuildings - their foyers and internal courtyards- are highly controlled and policed. On waste-landsites around the periphery of the city are the informal settlementshousing the poorestof the country'sinhabitants(Figure 2.5). These
Summary • Towns and cities are often formed around natural features,such as ports or river crossings. • Urban designersneedto pay attentionto the manner in which natural features have played a part in a city's evolution. • Open spacesare often vulnerable to development pressures.
Developmentprocess Placesare formed through the developmentof buildings and other structures. Since buildings involve highly complex and valuable arrangements of materials,servicesand spacesit is not surprising that their form is heavily influenced by relationships of ownership and control as well as political processes and cultural practices. Becausemany settlementsin the westernand eastern hemisphereshave grown around ancient routes, pastrelationsof powerandpolitics havehada profound effect. Kostof (1991) describeshow field patternsoften formed the initial template for a street layout that is describedas 'organic'.The term 'organic' has cometo be connectedwith planninglayoutsthat are low density Figure 2.5 The high towers of Jakarta'scommercial centre andoften picturesqueandit is unfortunatethat they also contrastedwith nearby 'informal' squattersettlements(Mike carry connotationsof an instinctive, vegetativeprocess Theis).
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Urban generators are normally one-storey-highdwellings, rudimentary and crudely built, with almost no control over the spacesaround them. In Unit 9 of this book, Chris Marsh explains the development process in more detail, with a workedexampleto illustrate how designers can work within the constraintsof the property market in Britain to achievea more liveable, humane urban form. From the discussionaboveit can be seen that developmenteconomicsis not an add-on to an understandingof urban form and urban design,but an essentialpart of it. As has been hinted at above, the relationshipsof ownershipand control of land and buildings also affect the public realm, i.e. the spacesbetweenand around buildings to which the public has access.There is increasingconcernnowadaysaboutthe privatisationof public space, i.e. the way in which 'public' spaces inside shopping centres and large public institutions havebeentaken into strict systemsof private management and control (Punter 1990; Davis 1992). Historically, there has always been a shifting set of controls over the public realm, dependentupon the current social and political structure.For example,the district of Bloomsburyin London was originally developed as a private venture and gates across the entranceskept out hoi polloi. While urban designerscannot changethe significant power relations of wealth and ownershipthat are generatorsof urbanform, they canhelp to influencethe shapeand use of the public realm to be of widest benefit. They can also proposedesigncontrols and guidelines which can regulate and shape development decisions. In Unit 12, Tim Townshend and Ali Madanipour discuss the types of design control that exist in Britain and in other countries at the moment and the arrangementsthat it would be desirable to have.
Urban types Although certain biological functions are common to all human beings, such as eating and sleeping, the manner in which even the most basic activities are carried out varies between societies and cultures. Eating and drinking, work, and familial relations vary significantly betweenstatesand continents.Societies and individuals may differ, but to function at all as cohabitingbeings,a certaindegreeof order and organisation is required. Patternsof order are played out through spatial organisation,inscribedinto the design of buildings and into the layout of towns and cities. Since many types of organisation are repeatedand thereis a benefit in repetitionin terms of economiesof thought, materials and labour, each society tends to evolve a seriesof urban types of which building types are an element.
Building types
The definition of a building type can be difficult in terms of making precisecategoriesfor particular historical influences,but as a generalconcept,the notion of type is useful. Perhapsthe most common type to notice in a global contextis that of the high-risetower. This is now found throughoutthe world, can accommodate offices, educational institutions and other public services,housing, shopsand other commercial activities. Somearchitects haveeven suggestedbuilding vertical cities in tower blocks. Clearly, tower blocks belongto different categoriesof type dependent upon their use. Other building types are less adaptable.Suburban low-density, single-storeyhousing is a form that is found throughout Europe and North America. This building type is less readily adaptableto other uses, partly as a resultof its constructionat low densitiesand partly due to the inflexibility oflayout. Whereasin preSummary industrial times, building types were closely relatedto In short, the economicsof the development industry their locality and dependenton local customs and materials, in the current age of globalised functions, largely control types are no longerplace-specific.This presentsboth a problem and an opportunity for the urban designer. • what is built and for which purposes,and The problem is that everywherecan look like every• who owns it and managesit. where else (Relph 1976; Zukin 1998). Some prototypes - types of city, city neighbourhoodor district, The developmentprocessalso influencesand is influtypes of streetor urbanplace,types of building - comencedby bine both spatial and functional characteristics. • the division of public and private spaceand its man- Particular activities, and the way these are managed, are associatedwith particularforms. The natureof this agement,and • local and central governmentintervention. relationshipcan changeover time but this is normally
Urban types a gradualprocess.More information on building types within a British contextis given in Appendix 2. Urban types as urban 'fabric'
Some urban designersfind it useful to considerurban typesas 'urbanfabric', making an analogybetweenthe backgroundof an urban structure and the warp and weft of a piece of cloth. Others make an analogy betweenurban types and the flesh or tissueof a body. 'Tissuestudies'involve the analysisof somecommon urban types in order to establishtheir characteristics. Thesemight be formal propertiessuchas streetwidths, plot widths, building heights,building shapesor footprints and the degreeof repetition of theseunits. Such
WANDSWORTH
AMSTERDAM
studiesof shapeand form, i.e. of the urban morphology, can fulfil a numberof purposes. At the level of training, by studying existing urban types, urban designerscan learn more about size and scale, which can add to their skills as designers. Drawing a spacewhich one has experiencedand properly understandingits dimensions and proportional relationshipsis a direct methodof learning. Often the scaleof a problemcan be assessed by superimposinga known urban area on a new site, as in the example shown in Figure 2.6, where an areathe size and shape of the Greenwich peninsula,which is the site of the Millennium Dome, is illustrated by superimposing areasof other cities onto it. Studiesof the urbanfabric can also be used in conservationwork, where, by studying the morphology of an area in its original
STAMFORD HILL
PARIS
Figure 2.6 Tissue study: a comparative analysis of site potential using known examplesimposedon the Greenwichpeninsula(John O'Leary).
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Urban generators form, proposalscan be madefor its improvementin a mannerthat enhancesthe original intention. This type of study has been pioneeredby architectsand designers in Italy, France and England (Moudon 1994) and has now become an acceptedtool in urban design analysis(seeUnit 6 and Appendix 2).
New urban types New urban types are emergingall the time as a result of technological and social change, and through a processof evolution, invention, purposefuladaptation and combination.The twentiethcentury is particularly rich in them, from modernistskyscraperoffice blocks and plazasand high-risehousingestatesto out-of town shoppingcentres,and from undergroundrailway systems to urban motorways.The urbandesignersthat are being trained today will be expectedto help develop the urban types of the future. They will need to consider what building types, systemsof transportation and arrangementsof urban spaceand form would be appropriateto life in the future city, and how these would be managed.This does not mean that existing urban types may not be used;often it is useful to draw on existing types but to consider them in new configurations. Summary • Sense may be made of urban developmentsby using the categoriesof both building and urban types. • The study of urban types as 'tissue' provides benefits to the urbandesignerin termsof addingto their knowledgeand skill base. • The notion of urban type may be used to develop strategies for conservation and in assessingthe scaleof new developments. • New types are emergingand presenta challengeto the urban designer.
Social and cultural meanings So far, space and buildings have been consideredas physical, functional entities, whoseexistencedepends on quantifiable measures,such as property values and traffic flows. The notion of type brings the idea of culture to the fore - that buildings might not only be shapedby the ritual relationshipsbetweenmembersof society at a particularchronologicaltime, but also that
a building typology is imbued with meaningsthat are emblematicof that regionor strataof society. It is not only buildings which carry theseproperties;the configuration of urban areas and urban spacesalso has deep layers of social and cultural meaning. These meanings are not clear and transparent,but may be various and contradictory (Franck and Schneekloth 1994; Massey 1994). A prime exampleof this is provided by the social housing built during the 1950s to 1970s, especially thosedwellings which are composedof blocks of flats. The imagery of such estatesin the media, in fictional representationson TV and in films, is generally appalling and suggeststhat drug dealing, burglary and assaultare commonplaceactivities. While somebadly neglected and badly managed estates undoubtedly suffer from the excessesof poverty, which includes criminality, this imagery might be unrecognisableto otherson different estatesof the sameera (Figure 2.7). Here the tenants might have fond feelings towards their flats, wry memoriesof the escapades of their children and a feeling of camaraderietowards some of their neighbours. Urban geographershavegrappledwith the different meaningsthat are investedin parts of the urban fabric and have noted that it is not simply that thesedifferent interpretationsexist, but that they also have an influence on the way that urban space is thought about, lived in and actedon by professionalsand politicians. For example,if peoplehave to walk in a place which they have learnedto think of as threatening,they are less likely to linger and more likely to move quickly throughit, trying always to be out of it as soonas possible. Furthermore,if there were a proposalto demolish the areaand rebuild it, objectionswould be lesslikely. In contrast,if a place appearsto be friendly and beautiful, as in a favourite streetwith somecharmingbuildings, people are not only more likely to take the opportunity to spend time there, but are also more likely to object to any drastic changesto it. At the presenttime, it is difficult for urban designers to do more than note that differential meaningsof spaceexist. Sucha recognitionhas the implication that even though a designermight produce a design that seemslogical and has elementsof charm, it could provoke quite hostile responsesin anotherperson,particularly a non-professionalwho does not sharethe same values or jargon. One way around this difficulty is to consultwidely on any designscheme(seefor example, Cowan 1998). This is not always possible,particularly when the people who are going to inhabit the space may be transientor come from very different circumstances.Another way of avoiding potentialproblemsis
Summary
Figure 2.7 What may seema hostile environmentto somewill be liked by others: social housing,London (Marion Roberts).
by trying to anticipate expectedresponses.By being awareof popular imagery, designersmay be in a position to challengecertain developmentdecisionsthat are basedon prejudice. Forexample,in Britain during the 19608 and 1970s, whole areasof by-law terraced housingbuilt at the end of the nineteenthcenturywere torn down as 'slums'.Eventually,throughthe action of campaigners,the positive attributesof theseareaswere recognisedand policy was changedtowardsrehabilitation. In Unit 10, Marion Roberts and Clara Greed consider some of the problemsdifferent types of individual might have in moving around towns and cities. Although thesemay be functional requirements,such as the needto avoid stepsfor peoplewith certain types of disability, they can also be connectedto the idea of ritual, meaningand management.The option of what is appropriate behaviour in any given place depends partly on internal controls which individuals learn through their upbringing, but also on externalcontrols such as policing. To end on a more optimistic note, it is important to affirm thaf changing the image of a place can often
have wholly beneficial effects. The city of Glasgow took this approach on a city-wide basis when they adoptedthe slogan 'Glasgow'sMiles Better'. Bycombining the slogan with positive design interventions, suchas an urbandesignstrategyfor the city centre,the revitalisation of the Merchant City and the regeneration of the Gorbals,Glasgow'sstatushasimprovedand events such as the Year of Culture in 1990 and the Year of Architecturein 1999haveraisedlevels of civic pride generally(Booth and Boyle 1993).
Summary • Spacesand placesare imbuedwith powerful meanings by different groupsof people. • Urban designersneedto be awareof the rangeand depth of thesemeanings. • Meaningscan vary betweensocial groupsand individuals, and be fragmentedand contradictory. • Meaningsand associationschangeover time. • Design interventions can and do change perceptions.
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BLOCK II APPROACHING THE DESIGN TASK
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Unit 3 The 'armature' and 'fabric' as a model for understanding spatial organisation
Bill Erickson
Introduction The previous units have looked at urban design as a processand at the forces which shapethe built form of cities. This unit will investigate how these can be brought together. The aim is to find a method of describingthe city, in particularthoseparts of the city that are the province of urban design.As discussedin Unit 1, an important part of any design process is analysisand problemdefinition, especiallyas so much of urban design is concernedwith existing situations. However, the samemethodmust also help us arrive at design solutions so it needsto be flexible and adaptable. Two such methodsare investigatedhere: the use of the grid and the urban armature. The task of urbandesignis not to designeverything in detail but to createa framework that will influence subsequentdecision-making.Where, then, do urban designersneed to place their energy to be effective? Obviously they need to have objectives, an idea of where urban development will lead, and how to improve the city for those who live in it. While thes.e aims may be social, urban designers'goals are physIcal. They needto concentrateon thosecomponentsin the city that will have the maximum influence on the subsequent development.The task of urbandesignis to createthe spatialpatternsthat will encouragepeopleto use and developthe city in a particularway. A practical first step towards a design methodis to distinguishtwo setsof urban elements: I The principal elementsare those that will have a
significant influenceon the form, structureor useof the city. 2 The secondgroup is much larger and consistsof the bulk of urban elements whose detailed configuration will not dramatically influence the overall patternor use of the city. The principal elementsare thosefeaturesto which the urbandesignerneedsto give specialattentionwhile the secondgroup can be more properly left to individual developersand designers.A simple way to distinguish thesetwo groupswould be to define the first group and describethe secondas everything else. In Block I the movementnetwork of the city was comparedto the arteries of the body. If this analogy is expandedto include, along with the arteries,the other 'vital organs' as well as the skeletonand nervoussystem,we might arrive at a descriptionof the principal elementsof the body.
Definition of the armature What featuresmight be included in a list of the principal elementsin urban design ternlS? One would sta:t with the main public spaces,the squaresand mam roads together with other transport arteries. To these one would add other places where people come together, such as community or religious buildings, and perhapsshopping areas and places of recreation also. Finally one might add the features that have a strong sharedmeaningand give local identity, such as
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The 'armature'and 'fabric' as a model monuments,landmarksandcultural institutions.Taken togethertheseelementsform a core aroundwhich the pattern of public activity revolves. That is not to say the principal elementsinclude all the buildings and spacesin public ownershipor control but rather those with a large sectionof the public as stakeholders.The term urban armature will be usedto describethis core, which can be thoughtof as a seriesof physicalobjects, buildings, spaces,roads,trees,monuments,etc., with a particularconfigurationor arrangement. The featuresof the urbanarmatureare thoseof particular concernto the urban designer.If the emphasis of designactivity is placedon the armature,what of the secondgroup of urbanelements- the broadmassof the city? Large areasof cities are often formed by districts where the nature of the buildings, spacesand streets have a high degreeof consistency.This is especially commonin residentialdistricts, e.g. suburbandistricts of single-family housesin cul-de-sacroads, rows of terracedhousesor apartmentblocks formed into grids. Here it is useful to return to the notion of urban fabric describedin Unit 2. Through the study of urban types andmorphologythesebroadareascanbe understoodin a genericway without the needto describeeverything in detail. This suggeststhat from an urbandesignpoint of view it may be that the design of the urban fabric requiresa differing processto that of the armature.
Establishing design criteria The initial stageof the designprocessis to set design objectivesandestablishdesigncriteria so that reasoned decisionscan be made.Designobjectivesare nonnally determined within the larger planning/development context and at the urban scale have a strong political and economicdimension. Differing parties may have conflicting objectives and the reconciliation of these may be controversial.For example,the design objective for property investorsmay be to maximisereturn on investmentwhile other groups may place greater emphasis on reducing social exclusion or ensuring environmentallysustainabledevelopment.While most people agreethat urban movementsystemsshould be efficient, differing objectives may place more or less importance on, say, public versus private transport. Less tangible objectives may also be important; for example,should the built environmentbe familiar and reassuringor new and stimulating?Designersmay also determineobjectivesthat are more generalsuch as the needto createenvironmentspeoplelike and feel comfortable in, or a desire for the built environmentto respondto the naturalenvironment.
Oncebroad objectiveshave beenoutlined they can be translatedinto more specific designcriteria against which particular design scenarioscan be tested. By way of exampleit is useful to take the seriesof urban generatorsset out in Unit 2 and examinethe types of designcriteria they may suggestfor a particularurban design project. This is an indicative list only and specific criteria need to be establishedin the light of particularcircumstancesand objectives. • Movement - enablesefficient movementof peopleand goods; - encouragesenvironmentally sustainabletransport modes. • lVaturalfeatures - encouragelife-styles that minimise the impact on the natural environment; - integratenatural and built featuresinto a unified system. • Developmentprocess - providesspacesfor a diverserangeof economic activities; - createsdemandfor investment. • Building types - provide appropriatebuilt fonns for modemlifestyles; - promote the developmentof built forms people understandwith a proven market. • Social and cultural meanings - createan environmentthat is easyto understand; - generatea rich local identity.
Design criteria are necessarybut design projects need design solutions as well. This requires method. The more numerousand diversethe criteria, the more difficult the design processbecomes.The design of cities has a long history and while a broad range of urban designtechniqueshavebeendevelopedover the yearsmany criteria haveremainedremarkablysimilar. This has led to the evolution of a number of longestablishedmodels for urban design which remain infonnativetoday. An exampleof sucha model, which can accommodateboth armatureand fabric, is given below.
Gridiron plan One of the most enduring and reliable urban design techniquesis the gridiron plan. One of the mostfamous and spectacularexamplesof this plan is New York, where the gridiron pattern was laid out nearly 200 years ago, and has proved an efficient basis for the developmentof one of the world's most successful
Urban armatures 23 cities. The advantagesof the grid are that it is quick to design,simple and providespropertiesthat are easyto subdivideand to sell. Thesearethe very designcriteria that have made the gridiron plan a popular design methodfor at least2,500 years(Figure 3.1). The form of many cities is similar despitethe differencesin the mannerin which they came about. In ancienttimes cities were often establishedas colonies. A group of peoplearrived at a chosensite and set about the task of laying a settlement,for which the simple gridiron plan provided an admirabletool. The basisof the methodwas similar and simple. It consistedof two seriesof straightroadscrossingat right anglesto form rectangularblocks. Most blocks werebuilt on but some were omitted to form public spaces. All that was neededwas a moreor lessfiat areaof land and a labour force. The plan could be laid out quickly using simple technology and most importantly it was easy to describe, record and remember. Despite its relative simplicity, the gridiron plan was robust and has produced places with a varied and vivid character.The overall size can be adjusted as needs dictate and it allows particular buildings and spacesto be given a privileged location by locating them on the main cross axes or around the forum. Finally, the rectangular block is well suited to most common building types and it proved a simple but equitablemethodof dividing land amongnew settlers(Mumford 1961).
Specifying the fabric The grid plan coupled with the use of standardbuilding typesis an effective methodfor the layout of urban fabric. It hasbeenadaptedover the last centuryor so to include more irregular patterns, as for example at Milton Keynes. The classic grid has all but been
Figure 3.1 A typical Romantown.
replacedin someinstancesby a new urban type - the cul-de-sac- in an attemptto soften the relentlessform of the rectilinear grid. However, culs-de-sacare connected together at more or less regular intervals to form a road pattern that can be thought of as a highly deformedgrid. The grid form itself provides a movementsystem. The designermight setout the grid or may describethe typical block. These blocks can be subdivided into standardplots aimed at particular sectionsof the real estatemarket. Particularbuilding types are frequently associatedwith certaincities, e.g. the New York brown stone apartmentbuilding, the London terracedhouse or the Hong Kong apartmenttower. Given that the urban designercan never design every aspectof the city, the useof urbantypes,particularly building types togetherwith streetand block types formed into more or less regulargrid forms (Figure 3.2), is a useful way to set out the natureof developmentone would expect to seein a particulararea.However, thereis a problem. The endlessrepetitionof similar units can appearbanal and can be confusingbecauseeach streetlooks much like another. What is neededis a method to activate partsof the urbanfabric, to createfoci, and channelsof activity that will makespecialplaces.This is wherethe urbanarmaturecan be a useful model, both as a way of understandingthe city and as an aid to design.
Urban armatures All settlementshavean armatureof somesort. In some cities the armatureevolves over time while in others it is designatedby those who first layout the plan. In most cases it is a combination of planned and unplannedeventsthat lead to the creationof the urban armature.In the example of the gridiron layout of a Roman colonial town one can see how the armature was envisaged,if not designedin detail, when the town was set out. The main roads which enter the city
Figure 3.2 Grid form shown as the repetition of blocks.
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The 'armature'and 'fabric' as a model through its gates lead directly to the forum. These streetsare the busiest,they are the broadestand they connect the city to its hinterland. Both citizens and visitors are likely to travel along them to reach the heart of the city. It is on thesebusy streetsthat shops will flourish. Dominating the vistas down thesestreets are large religious and civic buildings, many of which surroundthe openspaceto which the streetslead. This is the forum. It is the economic,social and symbolic heart of the city. It is a spacethe people sharein their daily lives in trade, religious ritual and governance.It is the spacein which togetherthey, or their forebears, sharedin the founding of the city. Such a city would have been meaningful to the inhabitants,comprehensibleto visitors and an efficient place to live, work, trade and if neededdefend. The key to this successis that the symbolic form, the legible features and the movement structure of the city reinforce one another. In fact they are, for the most part, madeof the samephysicalfeatures.The principal streets,temples,civic buildings and public spacesform a core of the city. This core, which is the locus of civic life, economicactivity and public utility, gives the city its identity. MacDonald(1986) refers to this core as an urban armature (Figure 3.3). Beyond the core lie the domestic buildings within which individuals live and work in private. Thus while at first sight the gridiron plan appearsuniform, it allows the principal elements of the city to gathertogetherto form an armature. As cities becamelarger, peoplefound it difficult to understandthe city as a single entity. What became increasinglyimportant was the experienceof the city as one moved through it and how one developedan image of the city as differing urban features were revealed.By creatingan orderedexperienceratherthan an ordered plan it was easy to reconcile imperfect geometries or awkward sites and to allow gradual developmentor rapid expansion. Movement through the city becamethe key to its understanding.The city was not to be understoodas a single entity; rather it was revealedto the pedestrianlike a narrative. This approachwas not a single devicebut, as Kostof (199I) puts it, a 'rich bag of tricks' that was rediscoveredseveral times during the subsequent centuries as a powerful techniquefor urbandesignand remainsso today.
Figure 3.3 Featuresof an urban armature.
relationship to the movement system is important. The papal restructuringof RenaissanceRome shows how the interventionsin an existing but ratherchaotic city were designedto make the armaturemore vivid and efficient. The restructuring was designed with movementin mind and it createda new experienceof the city at the same time as making the movement systemmore efficient and easierto comprehend.The new streetsbecamethe favoured sites for palacesand retain to this day the city's most fashionable shopping. This is one of the most important lessonsthat can be drawn from this type of intervention: if the structureis strong and appropriate(i.e. vivid, legible, meaningful and efficient) it will generateactivity and will be long lasting. The approachadoptedin Rome was adoptedacross Europe during the seventeenthand eighteenth centuries, not simply because it was fashionable but becauseit could function at the metropolitanscale of the expandingcapitals.This enabledlarge numbersof peopleto live, trade andmove aboutthe city while creating a very vivid public impression.This approach, sometimesknown as the 'Grand Manner', reachedits most dramatic in the nineteenth-centuryrestructuring of Paris (Figure 3.5). The technique can operate at a variety of scales from the metropolitanto the local. The basicprinciples are straightforward andfor the most part concerned with making a vivid armature:
• Large public spacesare createdat strategicpoints. • Thesespacesare connectedby broad straightroads Axes and movement (boulevards) which enable movement as well as visual connections. The armatureis an urban structurethat is experienced • Thesevisual connectionsare reinforcedby the erecthrough movement.It is composedof spaces(streets tion of monumentson the axes of streets which and squares) and of objects (buildings and monuleadsto the use of radial patterns. ments). The juxtaposition of elements and their • The main squaresand streetsare the favoured sites
Axes and movement
Papal interventionsin Rome Between about 1550 and 1650 a number of 'interventions' were undertakenin Rome by the powerful popesin an effort to make Rome the most beautiful city in Christendom.The most dramaticwas the constructionof the new St Peter'sCathedralwith its sweepingcolonnadesenclosingthe vast Piazza.However, a numberof other projects were undertakenas well. Many took the form of new streetsopenedthrough the existing congestedcity (Figure 3.4). The various projectsfocusedon principal churchesbut creatednew public spacesaroundthem so they could be seen.Thesespaceswere linked togetherby a seriesof new axial streets.Thesestreetsallowed efficient movementin the city and connectedundevelopedland into the city network, allowing the city to expandas well as creatingnew routesthrough the city. Monumentswere erectedto articulatethe arrangement and to act as signposts.Theseurbaninterventionsdealt almostexclusivelywith improvementsto the urban armature,and some, such as the famous SpanishSteps,were very dramatic. The less public areas were allowed to developin their own way but this developmentwas given new impetus bythe creationof the new and efficient urban structure.It embracedundevelopedareas,drawing them into the urban core and enablingthe city to expand.At the sametime the structurereinforcedthe symbolic understandingof the city and bolsteredthe political and economicpower of the church.
o I
500 I
1500 2000 2500 m I II
Figure 3.4 Eighteenth-centuryRome, showing the ancient street pattern and interventionsof the fifteenth and sixteenthcenturies.
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The 'armature'and 'fabric' as a model
Figure 3.5 Features of the 'Grand Manner' design method (Bill Erickson).
for public buildings which tend to be formal and grandiose. • The spatialcontainmentof the public spaceis codefied; building lines and heights are controlled by law. • The architectural treatment of buildings is controlled and co-ordinatedto createa consistenturban image. • The resulting urban structure (the armature)gives scale to the city as a whole and enablessmaller local developmentsto relateto its parts.
efficient connectivestructurefor the armaturewith a simple block pattern for the remaining secondary areas(Figure 3.7). We can seesuch an attemptin the
As a result of the restructuring of nineteenthcenturyParis, much of the city was completelyrebuilt, requiring the forced displacementof large popUlations which would be unacceptabletoday. However, the resulting urban image has given Paris a reputationas one of the most beautiful cities in the world with an extremely robust structure that guides contemporary urban projects. The monumentsand boulevardsform an integrated public structure which operatesat the metropolitan scale across the entire city, making it 'legible' and connecting individual districts (Figure 3.6). The plan of a typical nineteenth-centurydistrict demonstrates,however, that the plans of the individual blocks and housesare contortedand cramped.The 'Grand Manner' seems at odds with the obvious advantagesof the gridiron, such as regular and convenient building plots. This highlights one of the central dilemmas of urban design: spatial structures which may be effective at one scale, say that of the armature,may not be suitable at another, say that of the developmentof the individual plot. An obvious answermight be to combine the two methods as an Figure 3.6 A boulevardin Paris with a vista (Bill Erickson).
Urban armaturesand the evolutionaryproject
Key Civic buildings Main frontages
Commercial activity #+44
Dense residential
Transit route
Figure 3.7 Featuresof a 'transit orienteddevelopment'.
design of relatively new cities, such as Washington and Canberrafor example.At a smaller scale,a similar approach has been advocatedmore recently by urban designers such as Raymond Unwin (1920), Leon Krier (1992), Ricardo Bofil (Broadbent 1990) and Peter Calthorpe (1993). Here an axial composition of streets,public buildings and open spacesis used as an armature,around which the more private areas are established,using a more regular grid-like composition.
Urban armatures and the evolutionary project Today much of the work of urban designersis concerned with interventions in the existing city rather than the creation of new settlements.Further urban
projects need to be flexible in terms of time and content. Generally the spatial patternsof the city, the streetsand the public spacessurvive far longer than any particular building and the use of an individual building may change several times during the lifetime of the building. The urban design task can be seen as that of shaping the core around which this urban activity can evolve in the future rather than a finished project with fixed and final detail in every respect. This is the main difference between the urban project and the traditional architecturalproject: the need to accommodatechange. Here it is useful to return to the notion of the urban armature as a way of defining the core from which the urban project will evolve. The armaturecan be thought of not only as a descriptive techniquebut also as a design tool. The components of the urban armature in the
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The 'armature'and 'fabric' as a model modem city will vary from place to place but a first attempt at a definition can be made from the analysis of the historical models described above. An urban armaturewill include those principal elementsof the built environment involved with movement, activity and cultural meanings. It is possible to distinguish arterial roads from local streets, shopping centres from housing districts, civic buildings from privately owned ones (Figure 3.8). A more complex definition of an armature for the modern city might be summarisedas follows:
5 gives identity to individual localities within the city; 6 reconcilesdifferencesbetweenspecialisedand collective uses.
The armature as a public structure 1 encompassesthe main componentsof the movement structure; 2 distinguishesand privileges those parts of the city in collective use; 3 is a structuring device for the urban fabric within which it is embedded.
1
The armature in relation to locality and activity 4 is articulatedgiving metre and scaleto the city;
Figure 3.8 A typical urban quarter.
The armatureas a reinforcementof imageand identity 7 includes the artefacts that render the city legible, imageableand memorable; 8 persistsover time; 9 links the city to its landscapeand ecology. Movement structure
The armature encompassesthe main componentsof the movementstructure:the arterial roads,the nodesof the public transportand key pedestrianroutes (Figure 3.9). It has been shown that the shapeof the movement network will influence the configuration of movement (Hillier 1996). The main roads are not always the quickest route. We all know the example of the 'rat run', i.e. a shortcut that makes a journey
Urban armaturesand the evolutionaryproject Several urban types have evolved, such as suburban residential development, where pedestrian movementhas been replacedby vehicular movement and the life-styles involved becomedependent upon the car. • Public transport. This is configuredand is highly nodal in that it forms a network with access at specific points. It may be by different modes such as bus, tram or rail, but the stopping points or stationsbecomesignificant in structuringthe armature. This nodal transportis combinedwith pedestrian movement to form radial zones around the stops. • Rapid transport. This connects one centre to another.We can think of these centresas making termini rather than stops in a network. Termini such as major rail stations form key nodes in the armature and are the points at which scale is Figure 3.9 Elementsof the armature:movement. changed.Often large volumes of pedestrianmovement are associatedwith these nodes. They may form significant elementsin their own right, often easier.Traffic plannersreact to it by controlling trafas specialised zones. An airport is one such fic and forcing it onto designatedroutes. This can be example: it generatesa large amount of activity described as configured movement, i.e. movement but may not be experiencedas being part of the patterns that are channelled into particular routes. city. The other important type of configured movementis public transport. The location of railway lines and stations is obviously fixed and the route a local bus 2 Public spaces takes is also configured. Channels of configured movement(freeways,railway lines, etc.) connect the The armaturedistinguishesand privileges those parts city at the large scale but locally may act as a barof the city in collective use.The principal elementsare rier. What becomesignificant are the points of interbuildings, spacesand institutions of public interest. change:bus stops, metro stations, airports and traffic They will include the main streetsand squarestogether interchanges. with the public buildings and institutions butmay also If dependenceon private transportis to be reduced then a rangeof local activities needto be within walking distance.However,if designerswant pedestriansto take a particular route they need to encouragethem rather than force them. Pedestriansfollow a patternof natural movement,i.e. they take the route that is the most obvious. We can distinguishfour types of movement and should seek to design for each in an integratedmanner:
• Pedestrian movement. This remains the most basic way many people experience the city. However, for most of us the range of pedestrian movement is constrainedand this is one way of defining an urbandistrict (Figure 3.10). • Private automated movement. The private car enables natural movement but at speed. This speed allows space to be stretched to the point where pedestrianmovementis no longer possible, which distorts the nature of urban districts. Figure3.10 Elementsof the armature:pedestrianmovement.
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30
The 'armature'and 'fabric' as a model LOOK FOR Busyroutes (vehicular, pedestrian, transit); pedestrianshortcuts;public transport nodes. TIP It may not be surprising but the mostdirect routesare the mostused.Peopletendto walk along routes with a clear visual destination.In designterms, if a particular spaceor streetis to attract pedestrianactivity it needsto be placedon an obviousand well-connectedroute. A short cut is more usefulthan a big attractor.
Movementspace The first componentof the public structureis open spaceof the public realm. The most basicfunction of public spaceis to allow accessto private buildings. This simple function is usually performed by streetsthat haveone of a variety of forms alley, boulevard, cul-de-sac,crescent,etc. Generally the movementspacesconform to a loosehierarchythat is usually determinedby naturalmovementratherthan size.
Placesof transaction In addition to its function as a place of movementthe streetis a place of transaction (MacCormac 1987). A typical high street retains its identity as a place of movementbut is also lined by shops.In this casethe street retains its physical coninclude privately owned buildings such as shopping tainment but there is a much higher degreeof intercentres(Figure 3.11). action betweenpublic outsideand private inside. Some Simple definitions of public and private are no authors refer to these spacesas having active edges longer easy. Issues of ownership, responsibility and (Figure 3.12; see Unit 4 for more discussion).In any control when conflated with access, mobility and urban area, while all the streetsmay be public, some safety make complex and plural understandingsof the are sites of far more intensetransactionand thesecan notion of 'public realm'. At this stage it is useful to be thought of as being of greaterpublic interest. This attempt a working description of the public realm, gives us a secondattributeof the core: the streetswith bearingin mind that the aim is to distinguishthosepria high level of transactionas well as arteriesof movemary elementswhich form part of the urban armature. ment. We could add to this the buildings themselves Here 'public' should not be thought of as public (the shops, markets, etc.) which people use in their ownership but rather places of collective interest or daily lives. sharedactivity. To this end severalcomponentsof the public realm can be identified and dealt with in turn. Places of assembly A third component of public They are as follows: realm is the spaceof assembly:the square.This is a • movementspace place of congregationrather than movement and is • placesof transaction more suited to transactionsof various types. It is a • placesof assembly spaceof community; the spaceof markets and infor• public and cultural buildings
Figure 3.11 Elementsof the armature:public spaces.
Figure 3.12 Elements of the armature: transactions,active edges.
Urban armaturesand the evolutionaryproject mal meetings; the place to promenadeor to sit and observe,an opportunityfor display, a placein which to seeand be seen.
3 Urban structure
The armature provides a structuring device for the urbantissuewithin which it is embedded.It will divide the urban tissueinto districts and provide the connective infrastructurebetweenthem. It will have a hierTIP To work well, public squaresmay have archicalrelationshipto the featuresthat structurethese conflicting characteristicssuchas being quiet districts. (awayfrom busyroads) but active (well When defining the urban armatureit is useful to connectedto the armature). Successfulsquares rememberthat it excludesthe bulk of the urbanfabric. are often locatedadjacentto, rather than The remaining massis frequently homogeneousand is bisectedby, main movementspaces. formed by the repetition of similar elements,most frequently rows of housesor blocks of apartments(Figure 3.13). Thesedistricts can be thought of as a predomiPublic and cultural buildings Since ancient times nately private realm. The form of this type of fabric is there has beena trend for civic activities to take place often bestunderstoodfrom a study of its elementsand in specific public buildings, e.g. parliamentsand coun- their typologies,the patternof blocks, streetsand typicil chambers,courts of law, libraries, schools.As the cal buildings. It can be thought of as large 'patches', institutions they housecome to be thought of more as each of which has particular physical and social services, these buildings are losing the significance characteristics. they oncehad as symbolsof social cohesion.It may be The armaturegives this massform as well as strucmore useful to think of cultural buildings, which could ture. Here one might usethe analogyof a tree and liken include the local schools,discos,clubs, fitness centres and football grounds as important sites of social LOOK FOR Areasof consistentmorphology; activity. These buildings and spaces,together with underlying patternsor repetitionsin the street sites of 'high culture', such as museumsand art galpattern; generic urban types,such as grids of leries, are shared by the community and should be terracedhouses,culs.de-sacof semi-detached given pride of place not only to reinforce their symhouses;1960sblocksofflats. bolic function but to ensurethey are easyto locate and use. TIP The designof the armature will normally proceedfrom the large scaleto the small; from the generalto the particular. However,in establishing the nature of the urban fabric one TIP At the local level it is frequentlyschoolsthat needsto start with the particular - the urban perform manyof thesefunctions.A schoolis a types- and examinehow they aggregatetogether physicallocation around which manylocal to form large areas. Thesetwo designprocesses networksare formedand muchsocial activity needto be undertakenin concert. is based.
LOOK FOR Busyroutes; active edges;places wherepeoplecongregateand interact; civic institutions (libraries, town halls, courts, etc); cultural places(entertainmentand art); schools.
TIP Not everyspacecan be exciting and active. Sometimesit is bestto try and concentrateeffort aroundinto key spacesand allow othersto be quiet by contrast. Figure 3.13 Elementsof the armature:fabric.
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The 'armature'and 'fabric' as a model the systemof branchesand trunk to the armature,and the leaves to the urban fabric. We can recognisethe form of a tree when it is denudedof its leavesbut the leaves without branches are no longer a tree. In describing or designing the armature we need to be awareof the points at which it might 'bud', i.e. how the pattern of blocks, streetsand plots and buildings will relate to the armature.
4
Scaleand articulation of parts
The annatureis articulatedgiving metre and scale to the city. The armaturewill breakthe experienceof the city into pieces,or localities, eachof which hasits own scale. It may also be experiencedat differing speeds, e.g. both as a commuterand as a pedestrian,the featuresof thesemovementsystemsinterlocking together. The armaturecan operateat a variety of scales.As one moves acrossthe landscapeof the city from one district to another, a distinct rhythm is established. Each district has a centre and a characterof its own. The processfor defining the armaturewill be similar at differing scales.Each district will have its own armature and the dominantfeaturesof thesewill combineto make the city-wide annature.Likewise, the featuresof a district armature will form the focus of a smaller armatureat the neighbourhoodscale.The urban armature is to a degree fractal, i.e. the form is similar regardlessof the scaleat which it is studied. As discussedin Unit 2, the mode of transportwill also affect one's experienceof the city. The various scalesof the armatureare to a large degreedictatedby the speedand type of movement.For example,at the local level the route to the transportstop will be a key featurein the local armature;it will generallyinclude a cluster of local shops and be oriented to pedestrian movement(Figure 3.14). The route of the bus or train will itself form a key route of the armatureat a larger scale, not only becauseit channels movement and activity but becauseit is the way in which the passengers experienceand rememberconnectionsbetween districts. In this way the nature of the transportmode will influence the configuration of the armature. The combinationof pedestrianand public transporttendsto form an armature similar to beads on a string while movementbasedon privatecarswill be moredispersed.
5
Locality and identity
The armature gives identity to individual localities within the city. The annaturewill not be uniform but
Figure 3.14 Elementsof the armature:local armature.
will have localisedpoints of intensity which will provide foci for individual districts. As we move through the city we move from one district to another. Each district may have its own centreand hierarchyas well as subtledifferencesin its building typologies,perhapsbroughtaboutby changes in topographyor the age of the buildings. Eachdistrict will have its own special landmarks and memorable features that give it its own identity. These features form the main elementsof the armatureat a local level (Figure 3.14).
LOOK FOR A pattern of district centres.
TIP Differing scaleis often associatedwith the form of movement:think of neighbourhood featuresas thosewithin walking distance,local featuresas a short ride or a long walk away, and metropolitanfeaturesas requiring a special journey. (SeeAppendix3 for further information.)
LOOK FOR Particular activities and urban typeswhich distinguishone district from its neighbour.(SeeMental Mapping overleaffor definitions of a district.)
TIP Seekto clusterfeaturestogetherto form areas of intensitylinked by distinct connections.
Urban armaturesand the evolutionaryproject Mental mapping
Mental mappingis aboutunderstandinghow and why peopleperceivea placein the way that they do. Everyone remembersplacesthat they havebeento andusesthosememoriesto orientatethemselvesspatially andpsychologically and to find their way around.Although therehasbeenconsiderabledebateamongurbangeographers about the validity and significanceof mental mapping,urban designershavefound it a u'seful methodof both heighteningtheir awarenessof the environmentand attemptingto understandothers' perceptions. The aim of mental mappingis to understandwhich are the significant featuresof the urban environment for orientation.This methodof enquiry cameto the fore within the field of urban designin the early 1960s, when Kevin Lynch (1960) publisheda study of people's perceptionsof the city, entitled The Imageofthe City, using a method derived from environmentalpsychology. His aim was to develop a structurewithin which individuals' mentalmapscould be classifiedand usedas a meansof developingdesignideason the city scale. Although the extent to which people use the structure for navigation is debatable,Lynch's categoriesare useful becausethey enabledesignersto categorisethe environmentin a mannerthat is not dependenton their specialistknowledgeand provide a rough accordancewith the categoriesthat non-professionalsare likely to use. Lynch devisedhis methodin order to encouragepublic participationin policy and was disappointedto find it usedprimarily as an 'experttool'. Lynch found that his intervieweescategorisedthe urban environmentinto five different elements.These categorieshave been reproducedin other experiments.The graphic notation system is that proposedby Alcock et al. (1985). Paths Pathsare routes through which the observermoves,e.g. roads, footpaths,railways and walkways. They are the meansby which peoplecan view the city and form their mentalmapsof it. Pathscan often be the strongest organisingelementin people'smental maps.
Landmarks
*
Landmarksare usually a definedsimplephysicalobject, suchas a churchspire, a tower, a domeor a hill. They are not enteredinto but serveas a point of reference.They may be either distantor local. The more familiar a journey is, the more frequently local landmarksare noticed and used. Edges Edgesare linear elementsnot usedor thoughtof as routes.They may eitherjoin two recognisableareasas a 'seam',or may act as a barrierbetweenrecognisableareas.Edgesmay take the form of intenselybusy roads, railway lines, cuttings and canals.
Districts Districts are medium to large elementsof a city which the observerwalks into and which havean identifiable set of characteristics.Thesemight be relatedto use or architecturalstyle. A district may be defined by what is exterior to it. Somepeopleorganisetheir mental mapsarounddistricts ratherthan nodes.
Nodes The term 'transportnode' is now commonly usedand carries someof the meaningsof Lynch's terminology. A node is a point to or from which an observermight be travelling and provides an event on the journey. It is characteristicallya major junction or interchange.It can also be a meetingof paths.Its key feature, unlike a landmark,is that it must be entered.In somedistricts a node providesa concentrationof activities, suchthat the node is the core of that district.
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The 'armature'and 'fabric' as a model landmark
LOOK FOR Large single-useactivities and their interface with the local area.
node
TIP Theseareasfrequentlyhavea large perimeterwith a low level of activity. Treat these perimetersas backsand bury the zone within other activities. Treat the entranceas an active front and try to combineit into the armature.
6
Single-useactivities
landmark node
pa th
34
The armaturereconcilesdifferencesbetweenspecialised and collective uses. Within a city there are large areas of specialised activity which differ from the urban fabric and often form gaps or large impermeable blocks within it. They may be sites of a particular activity, such as factories, sports stadia or hospitals. The entrances may presentan opportunity to createsomeinteraction with local districts but frequently high levels of traffic can make this difficult. They may constitute elementsof the armature at a large scale but not at the local scale.
district
edge
pa
th
Figure 3.15 Elementsof the armature:urban image.
tical use. Theselandmarksare obviously key features iF! the urban armature.
8
History
The armaturepersistsover time. All the elementsof the armaturewill alter over time but many will persist and form permanentfeaturesin the cultural landscape, linking the city to its history. The city recordstracesof 7 Legibility its own history, including its origins. Throughoutthe city are echoesof decisionspeople have taken in the The armatureincludesthe artefactsthat renderthe city past. While the buildings may have gone, the boundlegible and imageable.The armaturewill include not aries betweenthem may survive. Buildings may outonly the featuresof utility but also those unique fea- live their usefulness and be reused or replaced. tures that are memorable, including landmarks and However, new buildings will be constrainedby the objectsof sharedmeaningsuch as monuments. shapeand size of the plot that accommodatedthe origBy adoptingKevin Lynch's definition of city image inal buildings and the alignmentof the streetthey face. (Lynch 1960), severalobvious elementspresentthem- A road may bendarounda tree long ago felled or a city selvesas candidatesfor inclusion in the armature(see gate long ago demolished.Rivers and shorelinesmay box). The importanceof movementspaces,or pathsas be infilled and city walls demolishedbut their influLynch would call them, has been addressedabove, as ence persists in the pattern of urban development has the importanceof nodes.Here the featurespeople aroundthem. Significant featuresof the armaturemay use to navigatethrough the city are at issue,in particu- in fact be absentbut manifestthemselvesin the historic lar those features which they distinguish as being effect they impose. memorable or significant. These may include landmarks along with pathsand nodes(Figure 3.15) . As people dwell in places,they come to associate LOOK FOR Local landmarks;streets,buildings themselveswith particularfeaturesof the environment. and spaceswith unique qualities. Likewise there are features they associatewith their neighbourhoodand with their city as a whole. Around TIP Usefeaturesto reinforce each other, place thesefeaturesgroup identities are formed and shared. landmarksat nodalpoints or at the endof main Famous examples include New York's Statue of paths. Locateplacesof assemblysuchas public Liberty, Sydney's Harbour Bridge and the Eiffel buildings andpublic squaresnear activesstreets Tower in Paris.Thesemonumentsare inseparablefrom and transport. the identity of the city but mayor may not havea prac-
Urban armaturesand the evolutionaryproject LOOK FOR Historic buildings;featuresthat havepersistedover time. (SeeUnit 6 for more information on historical analysis.) TIP The history of tomorrow will include objects madetoday. If they are to be robust, buildings and spacesneedto be pleasingand adaptable.
9
Landscapeand ecology
The annaturelinks the city to its landscapeand ecology. The armature can reconcile the city within its
natural landscapeby combining key features of the landscapewith the urban image. The urban landscapeis dominatedby the artificial, but this human-madeenvironmentis imposedacrossa much older natural landscape.Monuments,landmarks and districts can as easily be naturalfeaturesas human constructions.In designingcities it is easyto retain the view to the distant mountain, or the riverside walk. Theseprovide opportunitiesfor people to experience the physical terrain in which they dwell. For example, in the designof Canberra,Walter Burly Griffin located key buildings on the crestsof small hills and provided broad avenueswhose axes aligned with the peaks of surroundingmountains(Figure 3.16). At the centreof
civic centre
market ceotre
wa
ter lake ax is
lan
da xis
parlianment hill
vie
wt
od
ista
nt m
oun
tain
suburbs
Figure 3.16 plan of Canbcrra
0
1
2 miles
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The 'armature'and 'fabric' as a model the city he createda lake which providedthe settingfor public buildings and recreationalspaces.The result is an urban composition that is well placed within its natural setting. The city is located not only in the physical landscape but also within an ecological system. The mannerin which the city interacts with its local ecological systemis of increasingimportance.The urban armaturemay articulate this relationship in a similar mannerto that in which it articulatesthe urban fabric. One response is to develop a network of 'green spaces'throughoutthe city (Turner 1996). Other ways in which urban design can interact with the natural environmentinclude responsesto climate. Design can improve local microclimates both internally and externally, perhapsby catching the sun or providing shelter from wind, thereby making placesmore userfriendly.
(a)
LOOK FOR Naturalfeatureswhich may form landmarks; water coursesand wildlife corridors. TIP Thesenetworkscan be likenedto separate 'green armatures'accommodatingparks, waterways,natural reserves,and even waste land. The points of interaction betweenthese networksand the urban armatureare vital as each has the potentialto revitalise the other.
Conclusion: the armature as an urban design tool The urban armatureis a tool that may be usedboth for analysis and in design. By helping to distinguish the key elementsof the city that are of specialinterest,its use enablesthe designerto give emphasisto particular features and to structure the urban project. While developingthe urban armatureas a structuringdevice the designeralso needsto rememberthe nature of the urban fabric in which the armature is embedded (Figure 3.17). As shown above,the use of urban types can be used to developan urban morphology that will be an adaptablemethodof specifying the urban fabric while designingthe armaturein more detail. Because the armaturecan be thought of at a range of scalesit can be used on projects of differing sizes and complexity, both in new conditions and within an existing urban context.
(b)
Figure 3.17 Student project for a development at Port Greenwich(courtesyJustineWest). (a) Local structure;(b) features of the local armature; (c) detail of the proposedurban form at a local scale(opposite).
Design can be divided up into two activities: 2 the designof the urban fabric; 2 the design of the armatureas an integratedsystem within the fabric. Urban types can be used to describethe typical morphology of the urban fabric. This is likely to result in aspectsof an urban project being resolvedto differing levels. Particular aspects,such as those features that are in the public realm, may be specified more pre-
Conclusion
A
B
A
2
2
B
E
1 A-A Figure 3.17 (c)
cisely. As one movesaway from the key featuresin the minimum of prescriptivedesign guidanceto establish design, less detail will be given, allowing more free- the maximum effect. The object is to encourageand to dom to individual developers.As we have seen,con- foster a particular direction rather than to enforce or trol of some aspectsremains essential,but this might prohibit. In this way the notion of the urban armature be achievedthrough the use of guidelines and codes can assist in deciding where to place emphasisand rather than detailed design. The task is to provide the where the designercan standback.
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The 'armature'and 'fabric' as a model
Check-listof design objectivesto makea strongarmature
The armatureas a public structure
1
The armature encompasses the main components(~f the movementstructure • Aim for a strong hierarchyof movementspaces. • To be effective the movementpatternshouldbe simple and direct. • Develop a typology of movementspaces,eachassociatedwith particulartype of movement.
2 The armature distinguishesand privileges thoseparts of the city in collective use • Placesof transactionsuchas shoppingareasand placesof assembly,e.g. public squares,shouldbe well integratedinto the movementnetwork to form a chain of active spaces. • Buildings in collective use should be accessible,visible and, where possible,associatedwith public spaces. • Active usesshouldbe gatheredtogetherto form intenseareasof transaction. 3 The armature is a structuring devicefor the urban tissuewithin which it is embedded • Ensurethat the componentsof the armaturehave a compactand clear structure. • An understandingof the patternof urbanfabric within which the armaturewill becomeembeddedwill enablean effective connectionbetweenthe two to be achieved.
The armatureas a locality and activity 4 The armature is articulated giving metreand scale to the city • Provide a systemof nestedstructureswhich act as armaturesat differing scalesdeterminedby the mode of movement. • Ensurethe armatureis structuredso that experienceof it as one movesthrough the city is brokeninto identifiable segments. 5 The armature gives identity to individual localities within the city • Collect elementsof the city into a compactcore to reinforce one another. • Createa clear distinction betweendiffering districts of a similar scale. 6 The armature reconcilesdifferencesbetweenspecialisedand collective uses • Treat large specialistelementsas districts in their own right and integratethem at the larger scale.
The armaturereinforcesimage and identity 7 The armature includesthe art(jacts which render the city legible and imageable • Provide vivid objectsand placesaroundwhich collective meaningscan be built. • Combinepaths,nodesand landmarksto reinforce other aspectsof the armature.
8 The armaturepersistsover time • Look for historic monumentsand tracesof historic morphologythat have persistedover time. • Provide newfeatureswhich can be usedflexibly over time and can contributeto a long-lastingimage. 9 The armature links the city to its landscapealld ecology • Identify key featuresof the natural landscapewhich could form a 'greenarmature'and link it to the built one. as water courses. • Where possible,retain featuresbasedon natural systems such
Unit 4 Making convivial places
Marion Roberts
Introduction
style that providesthe ideal solution. Designersneedto considerthe relationshipsbetweenactivities, buildings Unit 3 introducedreadersto the conceptof the arma- and spacesin order to promoteconvivial experiences. Copenhagenprovidesan exampleof a city that has ture, both as a device for analysisand as a designtool for structuring urban areas. Although it has been achieveda great pedestrianconviviality. Advised by arguedthat the armaturecan operateacrossa rangeof the Danish urban designerJan Gehl (1987, 1995), the scales,as a designtool it provideslimited guidancefor City of Copenhagenproducedpolicies that are hostile the creationof lively, convivial placesat a local level. to cars and friendly to pedestriansand cyclists, and This unit will addressthis issue, drawing on the ideas traffic has remainedstable in the city for the last 30 of a numberof authors(e.g. Jacobs1992; Cullen 1988; years.Eighty per cent of all journeysundertakenin the Bentley 1996; Montgomery 1998). The unit will pro- city are now on foot. The populationof the city centre vide a brief pointer to somekey ideasfor designstrat- has risen. Gehl confoundshis critics with images of egiesratherthan an in-depth exploration;readerswho people sitting in parks, streetsand squares,looking at requiremoreexplanationare recommendedto return to each other, and looking at the view (Figure 4.1). He even showspeoplesitting outdoorsat cafe tablesin the the authorscited in the text.
The pedestrian experience One of the reasonswhy car driving is attractive is because the pedestrian experience has become unpleasantin many towns and cities. Some features that contribute towards a hostile environment for pedestriansare: • close proximity to heavy traffic with fumes and noise; • open, exposed routes with indeterminate spaces which are neitherpublic nor private; • lack of other people and activities adjacentto the route. At the local scale,urban designerscan interveneto eliminate some or all of theseproblems.It should be notedthat thereis no preferreddesignconfigurationor
Figure 4.1 People sitting, waiting and generally 'hanging out' in a squarein Stockholm(Marion Roberts).
40
Making convivial places play or people working. Even in a single-function housing estate it is possible to have more active frontages by, for example, including gables and bay windows, or positioning windowsso that a glimpse of the interior can be given without an invasion of priLOOK FOR Narrow pavements;excessive vacy. At the next level of interaction,an activefrontage traffic; obstructionsof various kinds. could encouragethe pedestrianto come in and make a purchase,view an exhibit, comein to worship or pay a TIP Imagine walking the streetsof any bill, for example. The most interactive frontages are masterplan or proposalsfor designguidancethat thosewhich spill out into the streetor the spacein front you make. Take measuresto providepedestrians of the building, as in cafes or bars, or shops that put with a comfortableenvironment. someof their merchandiseoutside(Figure 4.2). It is not possible to arrangefor highly interactive frontagesin all locations.They are mostlikely to come into being at points along the 'armature'of the urban Active frontages structureat different scales.As Bill Hillier (1996) has Unit 3 hasalreadyemphasisedthe importanceof active pointed out, cities have their own 'movement edgesor frontagesin making a place 'peoplefriendly'. economies'whereby people make journeys from oriThe term 'active frontages' implies a relationship gins and destinationseverywhereand it is at the points between the ground-floor uses of the buildings that where most journeyscoincide that active frontagesare frame a space or a street and the people walking most vital and will be self-sustaining.These are the through or generally 'occupying' it. The term 'trans- 'hot spots' within the town or city. Providing for active actions' (also explainedin Unit 3) is important here. frontages is patticularly important in making new An active frontage is one that allows some kind of public spaces,or in re-animating existing ones. The movementor visual relationship between the person encouragementof cafes and bars has been important outsideand the activity inside.At its most minimal, this for the revitalisation of many public spaces,for as might be one of simple observation,e.g. a window dis- Montgomery(1997) notes,cafesprovide 'a spaceto be middle of winter with blanketswrappedaroundthem, therebyrefuting the propositionthat a lively streetlife is only possiblein a warm climate.
Figure 4.2 This streetin westLondonmay appearuntidy andhastoo muchtraffic, but it hasmanyactivefrontages(Marion Roberts).
The importanceof mixed uses
Figure 4.3 The green areasin this inner city housing estateare devoid of life and meaning(Marion Roberts).
private in public'. However, a 'cappuccinoculture' is not the only way to create good places. Street stalls give life and vigour to a public place, as do places where children can play safely, bencheswhere people can sit and watch each other, or the provision of art works and sculpturesthat everyonecan siton or touch; the possibilitiesare endless. An importantingredientin the creationof animated spacesis an overlap and congestionof activities. Very few peoplewill sit on a benchon a green spacein the middle of a housingestate(Figure 4.3), but peoplewill be sitting jammednext to each other and on the walls of flower beds in the middle of a lively squarethat is surroundedwith life and activity. Labelling one urban plot 'cafe' in a block of otherwise mono-functional spacewill not ensurethat the animation sought for is achieved. Thinking aboutthe active frontagesof buildings has a further implication. If the public realmis to be public, then, by definition, some spaces are definitely not pUblic. Examplesof thesemight be back gardensand the service yards of buildings. This means that the 'fronts' and 'backs' of buildings need to be distinguished. Many problems have arisen on housing estatesof the post-warera where it is not clear where the front of the dwelling is and whetherthe spacethat surroundsit is 'public' or 'private'. Some of the most unpleasantstreetsin city centresare those which surround what are essentially the 'backs' of buildings, suchas the exteriorof an inward-facingshoppingmall. To createa lively public realm, it is importantto ensure that the 'backs' of buildings do not addressit.
LOOK FOR Examplesof existing 'active' edges; fronts and backsof buildings. TIP Checkdesignproposalsfor usesand activities aroundpublic spacesandfor fronts and backsof buildings. The simplestarrangementis for backsto face backsandfronts to face fronts.
The importance of mixed uses JaneJacobs(1992) was the first of the new wave of urban critics in the 1960s to decry the scientific approach to planning prevalent in the Anglo-Saxon world at that time which parcelledout land in singleuse zones.Her position was supportedby Christopher Alexander (1966) and later by other critics of the modern movement. The arguments against dividing land up into areasthat haveone land use such as housing or offices are as follows: • Single-usezoning encouragescar use becausethere are long distancesto travel betweendifferent functions. • Large areasof mono-functionalzoning causedifficulties for peoplein carrying out the different tasks they have to combine in a day - typically working motherswith children who have to combine working, child-careand shoppingin order to survive. • Single-usezoning encourageslow densities with consequentinefficienciesin public services(lack of public transport,shops,etc.).
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42
Making convivial places • Single-usezoning encouragescrime becauseareas are only used at particular times of the day (e.g. offices during working hours), making it easierfor burglarsto operate. • Single-use zoning lends itself to boredom and monotonyin aestheticterms. In the discussionof active frontagesin the last section, it was seenthat a mix of usesis a necessaryprerequisite for the provisionof activity. It is rarethat a cafeor restaurantcan occupymore than the first two floors of a building anda similar argumentappliesto manysmaller retail outlets. This implies a horizontal layering of activities throughouta streetor urban block in certain places,ratherthanhavingeachblock or blocksof building allocatedto one use. This is not to suggestthat all parts of the urbanfabric shouldcontain an intensevariety of mixed uses.Someareasneedto havea predominanceof one use, but even so would be more pleasant placesif there were at least a sprinkling of other uses. Jacobsand Appleyard(1986) describethe ideal zoning map as being a constellationof coloured dots, where eachcolourrepresentsoneuse.In someareasof themap, onecolourwould dominatebut otherswould be present. This meansthat in a housing area, for example,there would still be spacefor start-up businesses andservices, small shops,eatingplacesand bars, and somediscreet backyardindustry.Along the main armaturesandin the central districts therewould be a greatermixing of uses and the colourswould be spreadout moreevenly. Urban designerscannotprescribemixed-usedevelopment in a British context (see Coupland1996 for a discussionof the difficulties). Othercountrieshavedifferent planning controls and regimesand the development industry is more comfortable with funding mixed-usedevelopment.Governmentpolicy in Britain is now moving towards the promotion of mixed-use developmentand, in this sense,urban designers,even at the level of studentprojects,needto challengefixed ideas and make proposals for lively, pedestrianfriendly spaces.
Scaleand grain Pedestrian-friendlyenvironmentsare thosethat have a scale to which human beings can relate. There is nothing more dispiriting than being confronted by a cliff of massivebuildings on either side of a wide street with what seemlike endlessspacesbetweenthem.This is not an argument against high-rise or large-scale building forms; rather it is an argumentfor ensuring that the scaleof developmentat pavementor walkway level is one in which pedestrianscan feel comfortable. Shopping mall designersunderstandscale and grain very well. They typically placelarge departmentstores at the end of their malls. These large stores act as 'magnets' to which pedestriansare drawn, past a number of smaller-scaleretail outlets, often on two levels. Here the large scale is configured so that it complementsthe smaller, 'finer-grained' fa
11,757.282
2,048,090
1,462,500
1,477,440
2,796.240 1,980,000 1,744.200 1,054,080 7,544,102
Residualland value (£)
6,658,270(2)
1,139,390
506,250
952,560
1,443,960 1,080,000 991,800 544.320 4,060,080
>Or 418,270
(£)
Profit
116 Urban desing and development economics
Conclusion proposal.Basedon considerablelocal marketevidence gatheredby the group on the ground, the schemeis imaginativeand intricate. Table 9.4 has been amendedslightly in order to highlight the main issues identified by the appraisal, which can be summarisedas follows: The residential and office elements are clearly financially well founded and yield healthy profits and land values,althoughthe office yield of 6.75% may be rather optimistic in a fringe location, in which casethat elementis somewhatover-valued. 2 The public houselrestaurantelement appears to make reasonable returns while the School of Photography,basedon a rent of £150 per square metre (psm) is certainly viable too. 3 On the face of it, therefore,the proposalis valuedat £54,500,375,with total costs and profits estimated at £42,743,093.This leavesa residualland value of £11,757,282.In fact, this figure is slightly exaggeratedin that the studentgroup applieda 20% on cost profit elementbut did not include the land cost. As a result, profit was underestimatedby approximately £1.5-2.0 million and land value over estimated by the same figure. Nevertheless, the commercialelementsof the proposaldo 'stackup', albeit with a little adjustmentto the calculation-a process which is of course constantly checked throughoutthe developmentperiod as actual costs and valuesbecomeclear. 4 The problem with the development proposal is obviously not the commercial elements but the sportscentre.Although the proposalis basedon the existing swimming pool site being available for commercialdevelopmentand it has been assumed that this may yield a further £2 million in profit, the new sports centre is being made over to the local authority as a community facility at no cost. While this is laudable, it makes little commercial sense. The costs of construction are estimated at over £6 million and that assumesthat the land in question has no value, which is clearly not the case.The effect on the appraisalcalculation is dramatic and noted in the bottom right cells of Table 9.4. Either £6 million is deductedfrom the developer'sprofit, almost wiping out any return, or the land value is reducedby the samefigure. On the assumptionthat the landowner would not wish to accept a much reduced land value, the developer must consider other options, which might include the following: • looking for some return on the sports centre from the local authority in order to offset the developmentcosts;
• running the sports centre fully or partly as a commercialproposition; • reducingthe size of the centreor simply making the land available to the authority but not the building; • reconsidering whether to include affordable housinginstead,which althoughnot highly profitable would yield a modestreturn. In effect, the appraisalcalculationin Table 9.4 has 'tested' this particular mix and scale of uses and the proposal will need to be refined in the light of the results,which is preciselywhat happensin reality. EDAW scoopsManchesterbrief EstateGa;:.ette, 9/11/96 Manchester'sprime shoppingcore, ravagedby the June bombing, will swing northwards under an ambitious£500m plan to createan extra 49,237m2 of shopping, leisure and open spacesin the city centre. Victory in the InternationalUrban Design competition went to a consortium headedby LondonbasedEDA Wand including architectsBenoy and Simpsonand surveyorsHillier Parker.
Conclusion Although the property investment and development industry is conservative,it is also responsiveto consumer demand and on occasions when consumer requirements change, the industry evolves. Just as mixed-usedevelopmentsare still in their infancy and ignoredby someinvestors,the samewould have been said of leisure developmentsfive years ago and yet today leisure investmentis booming. A recognitionof the 'value' of urban designby the property industry is also in its early stages,but the signs are promising. • Joint professional approachesare emerging and awarenessis increasing. • The needfor a 'quality' propertyproductis appreciated and increasinglydemandedby more discriminating occupiers. • The legacy of the last recessionhas forced developersandinvestorsto recognisethat blandcharacterless buildings and environmentsare more vulnerableto marketfluctuationsthan interesting,vibrant, characterfullocations,all of which is encouraging. Given time, the property developmentand investment processwill help deliver better quality buildings and urban design,but not without professionalhelp.
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Unit 10 Evaluation and user perspectives
Clara Greed and Marion Roberts
Introduction This book seeksto provide guidanceon 'doing urban design' in a variety of locations,as opposedto considering the issuesthat surroundurbandesignas a field of study. The purposeof this unit is to suggestto readers various ways in which urban design proposalsmight be evaluatedfrom a userperspectiveand to explore in greaterdepth variations in cultural attitudes to urban design proposals.To illustrate this, and to alert the reader to these dimensions, we will revIsit Clerkenwell. The account will be interspersedwith examples from the wider national and international context of urban design.The purposeof this unit is to raise awarenessand encouragethe readerto think laterally about how the social agendamight be borne in mind within the urban design process,rather than to offer prescriptive standardsor rules. At least, it is hopedthat this approachwill encouragelateral thinking, reducepotentialblind spots,and openthe readerto a more comprehensiveview of urban design.
A framework for evaluation At the start of this book it was suggestedthat students set themselvesdesign objectives for each set of proposalsthey wish to make. The most obvious sourceof evaluationis providedby thoseobjectives,and readers are advisedto return to them throughoutthe courseof the designprocess. In the world outside the academe,when proposals are implemented, others make judgementson those proposals.Different interestgroups are representedin
the design process,as is demonstratedin Units 9, II and 12 of this book. Often, those who will inhabit the area, either as employersor workers, or as residents, cannotbe consulteddirectly becausethe site is empty. Similarly it can often be difficult to consult the wider community within which a developmentis placed.For example, a transport interchangeand its hinterland may be usedby literally thousandsof peoplewho pass through it every day, some of whom may also use its immediatesurroundingsin termsof the shops,barsand other facilities which may be locatedthere. To consult these potential 'consumers',although possible,raises considerabledifficulties. Designers therefore have to take on a wider responsibility towards their fellow citizens in the defenceof civic virtues. Thesemay be difficult to think out from first principles, but Punter(1990) provides a distillation of the work of nine authorswhich he suggests are the 'ten commandmentsof urban design'. Table 10.1 sets out a series of evaluative measures which are basedon Punter'sown table, including some additions.Considerationof eachof theseheadingswill enable readersto evaluatetheir own projects and to refine and improve their designs.The priority that is given to eachquality will vary, dependingon the project brief, the nature of the task and the student'sown intentions.
Clerkenwell The proposalsfor Clerkenwell will be evaluatedwith regard to the qualities listed in Table 10.1. The proposalshave already been evaluatedagainsttheir own
Clerkenwell Table 10.1 Evaluativemeasuresof urban design Quality
Brief description
Placemaking Relationshipto historical context Vitality
Appropriatespacesand activities Dialoguebetweenhistory and context Mixture of uses,pUblic-private interaction Quality of public access, movementsystems,accessfor disabled Relationshipof parts to surroundings,to eachother, to humanactivities and to senses Legibility, hierarchyof routes (where appropriate) Ability to respondto change Sensorydelight Surveillance,protection Social justice, empowerment (where possible),social mix Costs,re-useof resources, phasing
Public access Scale Articulation Adaptability Stimulation Safety Community process Efficiency
but not identical social indicators),5% of the total UK population are classified as belonging to an 'ethnic minority', 67% of the population have driving licences,and slightly lessthan the Islington sampleare over 60 years of age, while the disability figure in Islington is higher than national averages. The proposals make an appropriate compromise betweenthe needsof the poorerexisting residentsand richer incomers. The provision of converted fiats aboveexisting shopsand a sportscentreto the north of the site relates well to the existing council housing estate.The loft apartments,offices andrestaurantrelate well to the recent gentrification which is gradually changingthe area. Studentsmay often wonderhow to incorporatesocial objectivesinto a proposal, and the Clerkenwellschemeprovidesan examplein the way in which it retainsan existing run-down Victorian terrace of shopsand a pub and enhancesfacilities with the proposal of a sportscentre.
Relationshipto historical context
design objectivesand againstthe criteria for development economics(seeUnits 8 and 9), In this unit, more considerationwill be given to other criteria which may be given higherpriority by otherinterestedparties,The purpose of this is to demonstratethat, in practice, urban designis a complex processwhich, in common with town planning, involves balancing competing interests, The Clerkenwell schemehas been chosen becausereaderswill be able to familiarise themselves easily with the proposalsand henceto understandthe detailedcommentsmore readily,
The relationship to Clerkenwell's historical context has been carefully consideredand formed part of the key objectives.The re-useof existingbuildings and the careful attentionto the morphologyand the townscape of the surrounding area have all been carefully and sensitively addressed.Readersshould bear in mind that 'relationshipto surroundings'is not just a form of words but in a real sensemeansstudying the context and using consciousstrategiesto addressit.
Placemaking
Vitality
Placemaking was a key designobjective and the proposalsrespondto this criteria well, creatinga definitive urbanform with coherentstreetsand spaces,The types of usesthat are proposedrelate to Clerkenwell'sevolution, e.g. the new types of residentialuse such as loft apartments and town houses. The School of Photographyis a rather specific proposaland may not be taken up in practice, butechoesClerkenwell'scraft origins. The other uses are all appropriate to Clerkenwell'sposition as a rapidly gentrifying district in an inner London borough,which despitesomeof its glamorous occupants,is actually home to some of London's more deprived inhabitants. For example, 20% of the borough'spopulationwere born outsidethe borough, 20% are over 60 years of age, 40% are carowners, and 13% have some form of physical disability or long-term illness. In contrast(using similar
Vitality was a key designobjective. The proposalprovides a good mix of public and private usesand of different uses. The potential clash betweenthe users of the pub yard and the inhabitantsof the loft apartments has beenresolvedby suggestingthat the yard is closed at night. The proposalto include facilities that would have night-time as well as daytime uses, such as the sports centre, offices, further education and the pub/restaurantwould ensurethat the objective of providing activities that 'peak' at different times of the day would be achieved.
Public access Public accessformed one of the key designobjectives of the proposals and has been carefully thought
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Evaluationand user perspectives through.The openingup of a new route from the south to the housing estate in the north provides helpful public accessfor local people.The establishmentof two east-westpedestrianlinks also helpsto 'mesh'together former enclaves.The key objectiveof providing greater permeabilitythroughthe site has beenachieved.More, however, could be said about theseroutes in terms of safety(seebelow). The proposalhasalso thoughtabout vehicularmovementand servicing.By making the new north-southroad both for vehiclesand pedestrians,the servicing requirementshave been met and vehicular movementthrough the site has beenrestricted. There are no suddenchangesof level proposed,so those with walking difficulties would have few difficulties moving around the site. The public buildings are accessibleby car, which again would help many disabled users. The town houses in Brewery Yard would posesomeproblemsfor somedisabledusers,as they are inaccessibleby car. The hard landscapingof Compton Square could be of positive benefit for wheelchairusers, providing them with an accessible, car-freeopen space.
Scale Scale also formed one of the design objectivesand in this particulardesigntask, formed part of the dialogue with history. The scale of the developmentand its spacesis also appropriatein that it is not 'cataclysmic' in JaneJacobs'terms, i.e. it is not proposinga wholesale demolition and rebuilding at a much larger scale. The proposals are for building shapes and public spacesof a size that forms a convincing enhancement to the surrounding 'grain', yet at the same time can accommodatecontemporaryuses.
Articulation A hierarchy of fronts and backs has been established throughout the site. This provides a greater senseof articulation in that the major route, St John Street,has been given further definition and importance,through the completionof a continuousbuilding fa