The housing would always be driven by local councils rather than centrally.
Central government sets the targets for new homes, which local councils then have to deliver. Locally the local Tory Party criticised another party for a development which was being considered which could have delivered 5,000 homes. They went very quiet when I asked who was setting the target for the number of homes for the local council to deliver.
will we actually need the homes? The population isn’t rising …
Whilst the population isn't rising that doesn't mean that we don't need more homes.
There's a couple of factors which can mean that we need more homes even though the population isn't increasing (although up until fairly recently it was).
First up fewer children per family, 5 families of 7 need fewer homes than 7 families of 5.
The number of older people (who can be more likely to live alone, for instance due to being widowed/widowered), as they typically live in smaller household than younger people, they are also likely to live in larger homes than those who are younger with the same number of people in the household (as an example both my parents and my wife's parents live in 5 bedroom homes when there's just two of them, whilst their children are likely to live in smaller homes (of the 5 couples 1 has a 5 bed, 1 a 4 bed, 1 a 3 bed and 2 live in 2 beds, only those in the 2 beds have no children).
The number of people getting divorced can also have an impact on the number of homes needed, as of people don't live as a couple they may then need 2 homes rather than 1.
Even in saying that, it's still quite a simplification, however it does highlight that things are more complex than just looking at the overall population.