London Borough of Hillingdon
Policy H2 of the new London Plan provides specific requirements for London planning authorities in respect of small sites (defined as those with an area than 0.25 hectares). The H2 policy reads as follows:
Policy H2 Small sites
A Boroughs should pro-actively support well-designed new homes on small sites (below 0.25 hectares in size) through both planning decisions and plan-making in order to:
- significantly increase the contribution of small sites to meeting London’s housing needs
- diversify the sources, locations, type and mix of housing supply
- support small and medium-sized housebuilder [sic]
- support those wishing to bring forward custom, self-build and community-led housing
- achieve the minimum targets for small sites set out in Table 4.2 as a component of the overall housing targets set out in Table 4.1.
B Boroughs should:
- recognise in their Development Plans that local character evolves over time and will need to change in appropriate locations to accommodate additional housing on small sites
- Where appropriate, prepare site-specific briefs, masterplans and housing design codes for small sites
- identify and allocate appropriate small sites for residential development
- list these small sites on their brownfield registers
- grant permission in principle on specific sites or prepare local development orders
Paragraph 4.2.5 of the London Plan states that "incremental intensification of existing residential areas within PTALs 3-6 or within 800m distance of a station or town centre boundary is expected to play an important role in contributing towards the housing targets for small sites set out in Table 4.2.".
Within Hillingdon, 4,203 hectares of the 11,570 total area (36.33%) falls within this category. Although the "Examination in Public" version of the plan excluded conservation areas from this designation, the "adopted" version does not.
The diagram below shows the location of these zones.
Area with PTAL 3+, or within 800m of town centre or station
Town Centre Boundaries
Green Belt, Metropolitan Open Land, or other protected open space
Under the 2018 'Examination in Publish' version of the London Plan, Hillingdon's small site target was 7,650 reduced by 61.44% to 2,950 in the 2021 adopted version.
Over the next ten years London Borough of Hillingdon needs to add a further 10,830 homes to its existing stock of circa 113,363. Of this figure, 27.24% are expected to be delivered on small sites.
If London Plan targets are achieved, in 2030 Hillingdon will have housing stock of some 124,193 homes. Of these, 8.72% will be from small sites.
Under policy H2.B of the adopted version of the new London Plan, boroughs are required to "prepare site-specific briefs, masterplans and housing design codes for small sites".
To the best of our knowledge Hillingdon has not yet commenced preparation of its small sites design code.
Comparison between 2018 'Examination in Public' and adopted versions of the London Plan
With around 43.20% of Hillingdon's 11,570 hectare area designated as either green belt or metropolitan open land, all of Hillingdon's future housing targets must be accommoodated within an area of 6,571 hectares. Assuming that most of the housing stock is also limited to these areas, Hillingdon's average density, once all new homes are taken into account, will be around 18.90 homes per hectare.
Had the Mayor of London maintained the housing targets from the 'Examination in Public' version of the plan, the equivalent average density in 2030 would have been 19.61 homes per hectare. That's an increase of just 0.72, or 3.78%.
Small Sites Permissions in Hillingdon
The following map shows historic small sites approvals within Hillingdon, for all applications resulting in a net gain of between 1 and 25 dwellings. This data comes from the London Development Database, here.