The opportunity for London is to make better use of its land to deliver more and better homes which, in turn, are better places for Londoners to live. The London Plan’s policies are evolving to address the capital’s housing crisis with positive changes already being made - this must continue. The impending Mayoral Election in May 2016 and subsequent full review of the London Plan provide the ideal opportunity for London government to prioritise this issue.

The scale of the opportunity

The London Plan encourages boroughs to exceed their share of the capital’s annual 42,000 new homes target through more intensive use of land, particularly in areas which are well connected by public transport. The current targets have been set based on the capacity of identified available developable land, but they sit well below calculations of housing need (49,000 – 62,000 homes per year). Clearly making better use of London’s scarce land is a key priority. The analysis below shows there is plenty of scope to achieve this.

A picture of how well land is being used in London can be established by looking at existing housing densities across the capital and public transport connectivity. As figure 8 below shows , having removed green spaces, the Green Belt and water, there are many areas that are well connected but have low densities.

^{Source: Savills analysis; PTAL data; Census 2011}

It would potentially help deliver more and better homes if a well-connected area with low housing density were to conservatively increase its overall density, including through better use of vacant and underused land, to match the average housing density of an equally well-connected area that has a higher housing density.

Applying this approach to the whole of London produces the results shown in figure 9. The table shows the number of new homes that could be supported, all other things being equal, within inner and outer London by conservatively increasing densities, in addition to the homes already present in each area. These figures have been compared to the current London Plan 10 year housebuilding targets.

^{Source: Savills analysis using TfL PTAL and Census 2011}

 FIGURE 9: how the calculation has been done

• Average densities have been calculated based on transport connectivity, which is banded across the capital from high to low using Public Transport Accessability Levels (PTALs);
• Where an area is low density compared to the average for that band, once green space, Green Belt and rivers, lakes and canals have been excluded, the difference between the average density for that band and the existing density in the area has been calculated;
• The difference between these two numbers for each area across the capital adds up to the total number of homes shown.

It is important to be clear about what this table shows. The figures are based on only building on brownfield land – all green space such as the Green Belt, squares and commons has been stripped out, as have rivers, canals and lakes. The calculation does not take into account actual local circumstances; such as the urban realm (including local infrastructure) and whether, or how, new homes might be built. It is ultimately down to the market and the planning system to assess this. However, it highlights the extent to which there is the potential to make better use of land in London by moderately increasing housing densities in well-connected areas. Such areas include, for example, large brownfield sites, opportunity areas and housing zones, which the GLA has already indicated as areas that have the potential to support higher densities. Some scenarios about how this could be implemented are set out below, recognising that in every case the opportunities for how densification is achieved will be different, but must always take into account the context of the local area (see Making Better Use Of Land).

Table 4 is a useful starting point to think about how London might meet and exceed its housing target. In total this exercise identifies notional space for approximately an additional 1.46 million new homes, approximately one million more than the current 10 year London Plan housebuilding target. For the reasons stated above, this report is not suggesting that this figure is deliverable. If, however, land could be identified and housing delivery expanded to build just 10 per cent of these one million notional additional homes over the next 10 years, then London would be able to increase its housebuilding target to 52,000 new homes a year. At this level, delivery would be much more closely aligned with housing need.

Challenges and constraints

In the analysis above TfL public transport accessibility levels (PTALs) are used to estimate the capacity within London to intensify land use. PTALs are however only one measure of connectivity. This measurement tells us nothing about train capacity, for example. A place can be well-connected but local train services may be overcrowded at peak times. Likewise, a well-connected location may not necessarily have sufficient social infrastructure such as school places or doctors’ surgeries to accommodate significantly more housing.

These issues are not insurmountable. Upgrades have already taken place on some parts of the Tube network, such as the Northern and Victoria lines. More are underway, for example on the District, Circle and Hammersmith & City lines, with improvements planned elsewhere, such as the Piccadilly line upgrade. Over the medium term, additional transport infrastructure will be added such as Crossrail and over the longer term potentially Crossrail 2. And where housing densities are significantly increased, this is likely to be done as part of a mixed-use development, delivering commercial as well as residential space. Where there is a substantial commercial offering this will help to generate local jobs and could, in some instances, draw a flow of commuters away from other busy areas of the transport network.

In terms of social infrastructure, intensifying land use can help fund better provision. Developer contributions, subject to the viability of a development, can play a part in delivering this infrastructure. More significantly, more intense land use will also generate greater tax intake in the shape of business rates and council tax contributions.