On: The hottest trend in U.S. cities? Changing zoning rules to allow more housing

[namibj]

But for that the density reachable without elevators (if you're ignoring accessibility; i.e., 4~6 floors plus basement) suffices.

And yeah, having the bottom floor be commercial is often effective. Even if it's just a GP's doctor's office.

Look at pre-WW1 urban core neighborhoods in Germany, for example.