07 July 2022

Small Sites Capacity Summary

The research

The detailed analysis of the small brownfield site capacity[1] in 10 urban settlements across England[2], aimed to demonstrate the untapped potential of small sites that councils are failing to recognise within their brownfield registers.

Overall Summary

• The analysis of the 10 largest urban settlements in England has highlighted that less than a quarter of the small brownfield sites suitable for housing are coming forward.
• 50% of councils in the study (Cambridge, Exeter, Manchester, Wolverhampton, & Leeds) are identifying less than 15% of their small brownfield sites.
• Our analysis highlights that there is the potential to deliver over 110,000 homes on small brownfield sites within these areas.
• This would reflect almost 70% of the Government’s overall target to deliver 160,000 homes on all brownfield sites.
• Councils are failing to recognise this capacity however, identifying sites capable of delivering just 25,000 homes (an 80% shortfall).
• The under-utilisation of brownfield sites in some of these areas is beginning to be recognised. Andy Street’s Brownfield Land Study 2022 highlighted the potential for 4,000 homes in Wolverhampton. Our study suggests the potential is even greater, with the capacity to deliver over 8,000 homes from small brownfield sites alone.
• The delivery of these types of sites in sustainable urban locations could greatly reduced the need to develop on green belt land. The housing capacity of small sites is over 6x larger than the combined number of homes completed on green belt land since 2015.[3] 

Summary in London

• Only around 1/3 of the small sites in London are coming forward for development.
• The SSPP research has identified an additional 1,200 sites across London that if delivered could unlock a further 43,000 homes.
• If these sites are delivered alongside the existing small sites allocated for housing delivery, London as a whole could help oversee a further 56,000 homes being built.
• This is the equivalent to all of the homes built by the GLA over the last 5 years.
• The additional small brownfield sites identified in the research are roughly equivalent to 300 full-size football pitches.
• 20% of London Boroughs failed to identify a single small site with the capacity for housing.

Appendix 1) how the research worked.

The analysis of small sites was undertaken on the analytics software Datscha. A number of key considerations were taken during this analysis. 

Key considerations:

1.  Sites must be sized between 0.08 and 0.25 ha

2.  Sites must be freehold

3.  Sites must be one of the following use classes – Office, retail, industrial, public property, leisure, hotels, Sui Generis

4.  Sites must be within a 3 mile radius of the centre of the chosen local authority

Once filtered, sites were then evaluated individually by MRICS/MRTPI personnel on their general suitability for future residential development. These factors included location, current use, historic and cultural sensitivities, as well as other more nuanced factors. Sites were also included where part of the land was suitable for development, where residential could be incorporated along side existing uses and where existing buildings could be retrofitted for housing. 

Following the analysis and shortlisting of suitable sites, a standardised density per hectare ratio of 250 homes per ha was attributed to calculate projected housing delivery for London. This was based on Pocket Living’s experience of delivering small sites and what densities are required to develop a viable site in London.

For all other areas outside London, a standardised density per hectare ratio of 150 homes per ha was attributed to calculate projected housing delivery. This was based on Create Streets’ optimal ratio to achieve gentle densities in urban locations.

Each location was assessed firstly on its brownfield register. The SSPP research then analysed additional small sites that had not been allocated within these registers.

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