You are here

Policy D6 Optimising housing density


  1. Development proposals must make the most efficient use of land and be developed at the optimum density. The optimum density of a development should result from a design-led approach to determine the capacity of the site. Particular consideration should be given to:
    1. the site context
    2. its connectivity and accessibility by walking and cycling, and existing and planned public transport (including PTAL)
    3. the capacity of surrounding infrastructure.

Proposed residential development that does not demonstrably optimise the housing density of the site in accordance with this policy should be refused.

  1. The capacity of existing and planned physical, environmental and social infrastructure to support new development should be assessed and, where necessary, improvements to infrastructure capacity should be planned to support growth.
    1. The density of development proposals should be based on, and linked to, the provision of future planned levels of infrastructure rather than existing levels.
    2. The ability to support proposed densities through encouraging active travel should be taken into account.
    3. Where there is currently insufficient capacity of existing infrastructure to support proposed densities (including the impact of cumulative development), boroughs should work with applicants and infrastructure providers to ensure that sufficient capacity will exist at the appropriate time. This may mean, in exceptional circumstances, that development is contingent on the provision of the necessary infrastructure and public transport services and that the development is phased accordingly.
  2. The higher the density of a development, the greater the level of scrutiny that is required of its design, particularly the qualitative aspects of the development design described in Policy D4 Housing quality and standards, and the proposed ongoing management. Development proposals with a residential component that are referable to the Mayor must be subject to the particular design scrutiny requirements set out in part F of Policy D2 Delivering good design and submit a management plan if the proposed density is above:
    1. 110 units per hectare in areas of PTAL 0 to 1; or
    2. 240 units per hectare in areas of PTAL 2 to 3; or
    3. 405 units per hectare in areas of PTAL 4 to 6.
  3. The following measures of density should be provided for all planning applications that include new residential units:
    1. number of units per hectare
    2. 2)   number of habitable rooms per hectare
    3. 3)   number or bedrooms per hectare
    4. 4)   number of bedspaces per hectare.
  4. The following additional measures should be provided for all major planning applications :
    1. the Floor Area Ratio (total Gross External Area of all floors / site area)
    2. the Site Coverage Ratio (Gross External Area of ground floors /site area)
    3. the maximum height in metres above ground level of each building and at Above Ordinance Datum (above sea level).

These built form and massing measures should be considered in relation to the surrounding context to help inform the optimum density of a development.

For London to accommodate growth in an inclusive and responsible way every new development needs to make the most efficient use of land. This will mean developing at densities above those of the surrounding area on most sites. The design of the development must optimise housing density. A design-led approach to optimising density should be based on an evaluation of the site’s attributes, its surrounding context and capacity for growth and the most appropriate development form, which are determined by following the process set out in Policy D2 Delivering good design. Policy H1 Increasing housing supply, Policy H2 Small sites and Policy H3 Monitoring housing targets set out requirements for increasing housing supply across London and identify locations where increased housing capacity can be achieved.

Infrastructure assessments should be proportionate to the scale of the development. Minor developments will typically have only incremental impacts on local infrastructure capacity, which should be addressed by boroughs’ Infrastructure Delivery Plans. Therefore, it will not normally be necessary for minor developments to undertake infrastructure assessments or for boroughs to refuse permission to these schemes on the grounds of infrastructure capacity.

The surrounding infrastructure of all types is a key element in determining the optimum density of a site. The capacity of existing and future public transport services, and the connections they provide, should be taken into consideration, as should the potential to increase this capacity through financial contributions and by joint working with Transport for London. Boroughs and infrastructure providers should also consider the cumulative impact of multiple development proposals in an area. In general, the higher the public transport access and connectivity of the site, and the closer it is to a town centre or station, the higher the density and the lower the car parking provision should be.

In certain circumstances, development will be contingent on the future provision of public transport, walking and cycling infrastructure. In many areas of London higher densities could be supported by maximising the potential of active travel. Those exceptional circumstances for which part B3 of the policy could apply include development being brought forward in areas where planned public transport schemes will significantly improve accessibility and capacity of an area, such as Crossrail 2, DLR extensions, extension of the Elizabeth Line, and the Bakerloo Line Extension. It may be necessary to require the phasing of development proposals to maximise the benefits from major infrastructure and services investment whilst avoiding any unacceptable impacts on existing infrastructure prior to the new capacity being available.

In order to support the Healthy Streets Approach, development proposals should take account of the existing and planned connectivity of a site via public transport and active modes to town centres, social infrastructure and other services and places of employment. Opportunities to improve these connections to support higher density development should be identified.

Masterplans and strategic frameworks should be used when planning large-scale development to create welcoming and inclusive neighbourhoods, promote active travel, enable the successful integration of the built form within its surrounding area, and deliver wider benefits to residents, such as access to shared amenity space and high-quality public realm.

The proposed design and management of the developments should be thoroughly scrutinised during the planning process in line with part C of Policy D6 Optimising housing density. The higher the density of a development the greater this scrutiny should be of the proposed built form, massing, site layout, external spaces, internal design and ongoing management. This is important because these elements of the development come under more pressure as the density increases. The housing minimum space standards set out in Policy D4 Housing quality and standards help ensure that as densities increase, the quality of the internal residential units is maintained.

Management plans required to be submitted with higher density development proposal must include details of day-to-day servicing and deliveries, and longer-term maintenance implications. Management plans should provide details on the affordability of running costs and service charges (by different types of occupiers). Costed plans should set out how management arrangements will work in mixed-tenure schemes and the way in which residents’ views will be taken into account in delivering affordable services.

Housing density has been measured and monitored in London over recent years in units per hectare (u/ha). Average density across London of new housing approvals in the monitoring year 2015/16 was 154 u/ha with the highest average density being recorded in Tower Hamlets at 488 u/ha. However, comparing density between schemes using a single measure can be misleading as it is heavily dependent on the area included in the planning application site boundary as well as the size of residential units. Planning application boundaries are determined by the applicant. These boundaries may be drawn very close to the proposed buildings, missing out adjacent areas of open space, which results in a density which belies the real character of a scheme. Alternatively, the application boundary may include a large site area so that a tall building appears to be a relatively low-density scheme while its physical form is more akin to schemes with a much higher density.

To help assess, monitor and compare development proposals several measures of density are required to be provided by the applicant. Density measures related to the residential population (part D of Policy D6 Optimising housing density) will be relevant for infrastructure provision, while measures of density related to the built form and massing (part E of Policy D6 Optimising housing density) will inform its integration with the surrounding context. Measures relating to height should be the maximum height of each building or major component in the development. Boroughs should report each of the required density measures provided by the applicant when they submit details of the development to the London Development Database.