This might be a Cold Take but I'll say it anyway: I think it should be illegal to major renovations to a house, apartment or otherwise without a code inspector being consulted and signing off on it.
Now to that end; I think it would be a tremendously good idea to both subsidize projects up to a percentage of their property tax value and give a tax write-off for companies can verify they're renovating and building to current building codes.
Obviously it's an idea in it's infancy and I doubt I'll be in office anytime soon, but I like to think I'd be the "just wants to fuck around with Tax Credits" guy