It does seem like a solution to solve some issues like urban sprawl, endless residential neighbourhoods and so on.
Difficult for me to understand the logistics of it as of now. Few points:
- regulations need to be put in place for people living in the building to not promote house extentions
- good architectural solutions to avoid creating monster neighbourhoods
- consider noise and disturbance that will be given to current residents: maybe some incentives for them would be useful (as for example, retrofitting/insulating their homes too, energy from PVs for the all building, community roof top gardens)
-perhaps use fast and GOOD building techniques like timber frames and CLT buildings
-Consider value of the apartments: would the higher, probably more panoramic view from the new build increase the dwelling price? if so, would it really help with the housing crisis? how can you keep it cheap and of good value?
- probably a building survey /foundation and ground surveys will need to be delivered before building, who is paying for them?
As a general idea it could work, a bit more thought needs to be put in it to avoid unwanted reactions.