08/07/2013 08:42 BST | Updated 07/09/2013 06:12 BST

Overly Ambitious Affordable Housing Targets Are Stifling Development of New Homes

The UK is in desperate need of more housing. In December 2010, Policy Exchange claimed that local house building was set to fall to its lowest since the 1920s. The problem is particularly acute in London. Here in the Capital during the mayoralty of Ken Livingstone, a rigid target of every development needing to comprise of 50% affordable housing, was self-defeating. It often led to fewer homes being constructed, or the creation of high density developments with rabbit hutch flats being a key feature. Mayor Boris Johnson has relaxed the targets, and has set out new guidelines in regard to the size of rooms, reminiscent of the generous 'Parker Morris Standard' room sizes that we saw in previous years. However there are still many - much needed - proposed applications for new homes that have yet to be realised.

In London, the population is forecast to grow to nine million by 2020, and at present, there are 180,000 developments that are currently stalled in the city. Overly ambitious affordable housing targets are stifling the development of new homes, and that is why I recently called for London's 33 local councils to take a flexible approach to affordable housing requirements where necessary, in order to get development moving and provide enough new homes for London's growing population.

As a member of the London Assembly, I have experienced first-hand the issue of targets for affordable housing affecting the ability of local councils and developers to realise new homes. Buildings have stalled partly due to over-ambitious affordable housing requirements, which were set in the past in very different financial times, but are now strangling these developments and taking away the resources needed to build them. This has so far prevented the development of hundreds of new homes and leaving eyesores in their town centres.

However, there is a successful way forward. For example, in my local area of Croydon we have managed to work with developers to restructure the previous affordable housing requirements of a key housing scheme, so that 183 new homes can now be delivered. So by asking for a little bit less, we can actually achieve much more.

I am in no way asking for a removal of the affordable housing requirement. I am particularly keen to see the rise of part buy/part rent schemes for first time buyers, but with London's growing population, we need to make sure that developers with increasingly thin margins can complete the new homes that London requires. Boroughs must not repeat the mistakes of the past by squeezing developers too hard, otherwise we risk choking off this vital supply of new housing. What is true for London will be true elsewhere in the UK, and the government, housing associations and local councils need to work together to have a realistic plan for moving the stalled house building industry forward.