Does upzoning work?

Does upzoning lead to new homes? Does it reduce the cost of homes? Michael Wiebe has an accessible review of the academic literature around upzoning in his living literature review, examining empirical studies on major upzoning cases in Auckland, Sao Paolo, Wellington, New York, and Zurich. Upzoning consistently increases the housing supply, and when studies are set up to measure the impact on prices, it brings costs down (at least relative to what would have happened without upzoning - sometimes that just means prices increase less fast). But the link between upzoning and these outcomes is a complicated one (as Alex has written about before); upzone in a place where building new housing requires a lot of demolition, and you’ll need to upzone by a larger amount to see a comparable effect.