Whilst cities compete for monumental developments, with the height of skyscrapers and the zeitgeist of project architects the key barometers of thriving urbanism, a quieter densification revolution is taking place. Within the gaps and shadows of our urban fabric, owners and small developers are cumulatively creating homes at a scale to rival the largest housebuilder and the most significant regeneration project.
One third of new urban homes developed between 2001 and 2011 in England were small-scale developments – so called ‘soft densification’ - including in-fill plots, residential sub-division of large homes into multiple flats, changes of use, and the creation of new homes in back gardens.
Soft densification is making a large contribution to urban housing supply, yet the cumulative impact it has upon our cities is not being fully scrutinised.
This level of small scale growth is equivalent to 31,000 new dwellings being built every year, or a city the size of Leeds every ten years. Surprised? This was the key finding of a study for Plan Urbanisme Construction Architecture, an agency of the French government, keen to learn from the English experience to support the growing densification of the wider Paris region.
In some cities such as Bristol, the signs are visible right across the city, with new homes being seemingly squeezed into every vacant small plot. In other urban areas – such as Ealing – the physical evidence may be less evident, with an unchanged street morphology hiding the substantial incidence of residential sub-division.
Soft densification appears to have three principal drivers:
- It is partly a response to almost 75 years of planning policy that aims to prevent urban sprawl: a policy position that continues to prevail alongside a strong culture of opposition to development on greenfield sites at the urban periphery.
- It is also a response to a broader acceptance that increasing urban densities has environmental and social advantages in terms of supporting service provision, particularly public transport.
- Yet it is also a story in many places of strong market performance. In locations like Ealing and Bristol, case studies for the PUCA analysis, there is a strong financial motivation behind small scale developments – there is money to be made - with even some evidence that developments in back gardens are seen as a new form of pension planning.
Yet the current focus of development control is principally on large scale developments with the impacts of small scale densification largely unaccounted for. This is largely because the level of interrogation of a planning proposal is often proportional to the scale of development.
...whilst developments at a larger scale make a contribution to the associated costs of development in a local area through Section 106 payments or the Community Infrastructure Levy, local authorities have little way of recouping the cumulative costs of soft densification.
Whilst this recognises the significant impact that large scale developments may have on a wide area, it may not recognise fully the cumulative impact of smaller developments.
This means that whilst developments at a larger scale make a contribution to the associated costs of development in a local area through Section 106 payments or the Community Infrastructure Levy, local authorities have little way of recouping the cumulative costs of soft densification. Infrastructure requirements resulting from increasing local population, whether public transport, school places, GP surgeries or local parks, therefore need to be met outside the development process.
Cumulative impact also change the character of neighbourhoods over time. This is particularly true where extensive residential sub-division occurs as neighbourhoods once predominantly occupied by families become populated by more transient communities characteristic of smaller dwellings.
Not all impacts are negative, though. Small scale developments can have positive impacts upon the viability of local businesses, the vitality of local shopping streets, and transport links while increased density leads to higher council tax receipts.
In urban areas the soft densification debate is highly dependent on the local context. In Ealing, there is very little public or political contestation, reflecting both the historic dominance of redevelopment and contemporary concerns about housing supply, which trump worries about the viability of local services. In Bristol, however, the pressures to densify, which are supported through the City Council’s planning policies, are meeting sterner resistance. In many neighbourhoods, local residents are concerned about the cumulative impact of soft densification on car parking, health services and neighbourhood aesthetics.
Soft densification is making a large contribution to urban housing supply, yet the cumulative impact it has upon our cities is not being fully scrutinised. Local authorities have limited resources to plan housing, to monitor development and to provide the necessary infrastructure.
Society may be focused on the impact of high-rise developments and the political tortuous debate about the need for and efficacy of development on greenfield sites, but in the meanwhile the tide of soft densification continues to rise.
Guest blogs may not represent the views of the RTPI.
Dr Richard Dunning, Hannah Hickman and Professor John Henneberry
Dr Richard Dunning, Lecturer, University of Liverpool
Hannah Hickman, Senior Research Fellow, University of the West of England
Professor John Henneberry, University of Sheffield