The socio-economic value of urban layout

The relevance of urban layout for placemaking has been published in strategic policy documents such as Paved with Gold (CABE). Based on such work, a team led by Space Syntax is developing an evidence-based urban layout evaluation programme able to overcome the barriers preventing layout factors being considered in economic appraisals.
Urban layout, and its effects on social, cultural and economic aspects of community, is an intangible asset, difficult to visualise and measure during the planning and design process. Although methods of quantifying and measuring the relational properties of urban layout within its context have been developed by researchers at UCL and other institutions, and used successfully within the new planning process, only a handful of Local Authorities and Regional Development Agencies make use of them.
A series of partnership workshops has identified themes where the impact of urban layout has been scientifically proven, and where tangible spatial design, social and economic indicators for the performance of layout can be found. Five themes were identified for further analysis.
• the value of property security Based on the analysis of burglary patterns over five years in a London borough, Professor Bill Hillier and Oezlem Shabaz at UCL identified four major layout factors that contribute to safer places. One of these factors reducing burglary risk is the existence of a residential culture, which can be measured by the number of dwellings per street segment.
• the value of personal security The same research shows three spatial factors that reduce the risk of street robbery, one of them being the relationship between sufficient movement rates resulting from an integrated spatial layout and residential culture measured by dwellings per street segment.
• the value of urban centres The recently published study Paved with Gold (CABE/Buchanan 2007) that showed the impact of street design on the economic impact in ten London high streets was complemented by a strategic layout component. It shows that successful urban centres have particular spatial features, for example significantly smaller urban blocks and higher accessibility streets that distinguish them from their context. Importantly, this study enables us to distinguish spatial effects and compositional effects.• the value of residential property Analysis carried out by UCL and Savills Research on more than 100,000 dwellings in a London borough showed that the distribution of residential property values, measured by council tax band data, follows a clear spatial pattern. A concentration of higher value properties is found at globally integrated places, where locally integrated places tend to have lower property values. Savills Research showed that tax band trends are in line with property sales.• the value of public realm design Based on the recently completed public realm improvements in the Walworth Road in Southwark, a before and after assessment of the detailed public realm has been carried out comparing the results of the Pedestrian Environment Review System (PERS2) with the spatial layout analysis. The case study also suggests a way to capture the health impact of a more pedestrian-friendly street layout through higher physical activity rates.
The new layout value tool calculates these indicators on the basis of simple Ordnance Survey maps. A set of GIS-based computer tools has been programmed by Space Syntax to calculate the indicators using available spatial and statistical datasets (Ordnance Survey, Office of National Statistics). The tools can quantify and monetise the socio-economic benefits of urban layout.
This project, known as IVALUL, has been supported by the
UrbanBuzz knowledge exchange programme.
For more details, please contact a.chiaradia@spacesyntax.com or c.schwander@spacesyntax.com
http://www.urbanbuzz.org/scommunities/homePage.do