Empty office buildings downtown. A housing shortage in almost every major market. Is there a way to address both issues at once by converting historic but underutilized office buildings into apartments and condos in city centers? It’s an idea that has been discussed, and in some cities, implemented in recent years. But while the idea seems simple enough—repurpose existing office space for residential and mixed-use projects—there are some real challenges limiting the feasibility of large-scale office to residential conversion.