Slow build out
Slow build out is described by the government as 'where sites have full planning permission, are being built, but the pace of building is slower than it could be under different development models and incentives. Multiple market studies have found that most large housing sites are built at the pace the homes can be sold at current second-hand market prices, rather than the pace at which they could be constructed if pre-sold (i.e. to an institutional landlord). The rate of building consistent with selling at local second-hand market prices is known within the industry as the ‘absorption rate’. The Letwin Review concluded that local absorption rates were a “binding constraint” on build out rates. The CMA observed, that “the private market will not, on its own initiative, produce sufficient housing to meet overall housing need, even if it is highly competitive”.' From the government policy paper "Planning Reform Working Paper: Speeding Up Build Out" published 25 May 2025.
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