The London Plan density matrix is over twenty years old and in that time has only had two minor review in 2006 and 2012
Yet since as early as 2006 the majority of new housing in London has had developments well above the matrix ranges?
It does little to help developers. Lets say you own an úrban’ site in PTAL5. So you can get 45-260 DPA depending on dwelling size, a huge range. In some cases where context is important developers will bid too much for land and it will squeeze out affordable housing. In less constrained sites developers might be able to get away with 300-500 DPA in actuality making the matrix a mockery.
The matrix derives from the 2003 SRQ report. This illustrated a number of housing typologies that could be designed to high quality. It was not based on a study of actual London fabrix – it was a low cost report – but case studies.
This approach has fallen well behind contemporary best practice in ‘bulk zoning’that is the planning for how much bulk of development per site, area and city.
- Examine the overall zoned capacity of a city
- Zone ás of right’ in the highest potential areas – see for example the recent initiatives of the California Governor or the recent pamphlet by the White House on this issue.
- Study the existing range of building typologies in the city and the potential for soft intensification like accessory dwellings (banned in London as ”garden grabbing’ – without realistic controls allowing them we simply get beds in sheds)
- Zone for acceptable forms, including where this would intensify existing areas, identifying areas for uplift – see for example Torontos policy on Medium Density Avenues.
- Policy to secure quality at density like the Superdensity report are important but they are complimentary not replacements for being able to secure a certain bulk as of right
- It is much better to control bulk through floorsapce, or at a pinch hab rooms, rather than number of dwelling – as this disincentivises a good mix of units sizes.
In short the revised London Plan needs to do four things
- On large sites including housing zones it should zone for high density as of right
- It should identify areas for uplift. including around stations and along bus corridors with outdated shopping areas
- It should identify low density public housing estates not suitable for conservation (Lambeth im looking at you) and zone them for high density as of right, major opportunities such as Tahmemead should be positively masterplanned as a strategic priority. There should be a policy of no net loss of social housing.
- Some of teh duller low density private areas should be zoned for uplift as of right, large parts of Havering and Hillingdon would fit in this category. There should be density bonuses for assembly 2 or more units and a London Plan policy to approve CPOs on hold outs by dwellings where it prevents larger comprehensive schemes.