Same thing here in Boston--three story detached houses, with one apartment per story, are the most popular form of housing here, and yet have been illegal to bu

Same thing here in Boston--three story detached houses, with one apartment per story, are the most popular form of housing here, and yet have been illegal to build for the past 100 years (with a few exceptions) due to being too dense for single-family zoned areas and being a fire hazard. It's odd that there is no "build out of non-flammable materials" exception for the latter.