A prior condition for building houses is having permission to build them. We have
found that the planning system is exerting a significant downward pressure on the
overall number of planning permissions being granted across Great Britain. Over
the long-term, the number of permissions being given has been insufficient to
support housebuilding at the level required to meet government targets and
measures of assessed need.
In particular, we have seen evidence of three key concerns with the planning
systems which we consider are limiting its ability to support the level of
housebuilding that policymakers believe is needed:
(a) Lack of predictability;
(b) Length, cost, and complexity of the planning process; and
(c) Insufficient clarity, consistency and strength of LPA targets, objectives, and
incentives to meet housing need.
We have also seen evidence that problems in the planning systems may be
having a disproportionate impact on SME housebuilders.
1) Green belt policies prevent the expansion of cities outwards. Compare the footprint of London to other major European cities and you'll see it's barely moved at all for decades.
2) Discretionary planning policies that mean local councils can turn down development, even when it adheres to stated rules. See for example this brownfield development in Brighton, a city that has one of the worst housing delivery records in the country: https://www.bbc.co.uk/news/articles/cwygkz57k1vo
The professional planning board recommended it for approval, but it was turned down by the political committee because of local complaints. A well specified zoning system would avoid this. Reduced uncertainty would make it possible for smaller builders to enter the market
3) affordable housing mandates (known as Inclusionary Zoning elsewhere). These specify that some amount of the new building must be offered at below market rates. Although there's a strong moral case for capturing some of the value produced by giving planning permission, this effectively acts as a tax on building homes in places with shortages. Ideally, people would be most incentivised to build where prices are highest, but this policy removes that incentive.
I can answer part of that. Very few areas are even opened up to allow building private housing, all kinds of "neighbours" can veto anything, just to name two problems
