Government-backed AI tool identifies over 3,000 sites with housing potential in Lewisham

Lewisham Council has identified an estimated 3,017 small sites with potential for 9,747 homes to be built using a government-backed AI mapping tool.

The ‘Small Sites AI Finder’, developed with architect RCKa, was a pilot within the fourth round of the proptech innovation fund – the Ministry of Housing, Communities and Local Government’s (MHCLG) flagship programme supporting digital innovation in planning and housing delivery.

The tool analysed land parcels across the borough and identified common types of small sites, such as infill, backland and side-street sites.

It also examined planning application data to understand the impact of Lewisham’s ‘small sites design guide supplementary planning document’ (SPD) on small site delivery. It reviewed applications submitted before and after adoption of the guide and found that approval rates increased slightly from 38.8% to 40.7% after adoption, while fewer applications were withdrawn. Refusal rates also increased and applications took longer to determine on average.

The council said these changes may reflect closer scrutiny of planning applications following adoption of the SPD, alongside wider factors including resourcing pressures and economic conditions.

MHCLG said the results of the programme “could inform future policy work and engagement with landowners and developers,” but warned that AI tools “cannot replace professional judgement.” The department added that accuracy ranged from 31% to 76% depending on the site type, with planning officers needing to review identified sites and cross-check them against the SPD.

Lewisham Council is planning to continue developing the Small Sites AI Finder to improve accuracy and functionality. It is exploring how the tool could support targeted engagement with landowners, inform future updates to the small sites design guide SPD and help identify opportunities to increase housing delivery on small sites.