The reasonable solution to this problem would be for government to give power back to local authorities to initiate the construction of social and affordable housing on the scale which is presently required in London, thus eliminating these mixed developments which, by the logic of all concerned, don't address the issue of housing for the poor. But we all know this will never happen.
Aye, in a hypothetical utopia the Affordable Home Programme would have worked. That's 2016?
But- "London" councils (largely the same across the South East) don't have the infrastructure in place to initiate this sort of work anymore, they have been decimated intentionally so they're completely reliant on external development. Even internal maintenance contracts are out to tender to private firms these days, and you tend to find that they can afford to undercut the council's internal teams/departments. Plus if you're a trade local government money is fuck all generally. Same goes for directly employed council staff.
So you end up with quasi-private departments running majority of capital programmes with embedded PC/PDs in place even on small scales when individual projects aren't necessarily CDM notifiable etc
There are very few "capital" departments with the capability to deliver this sort of programme without large scale developers getting involved and where is the incentive for a private firm to do this with no external sales to maximise their profits.
Councils build council property is all pie in the sky stuff that would require top down organisation with billions of investment to put it in place. Ultimately in shit jobs its easier to use a big firms liability insurance and get them to enlist everyone on your behalf