Accessory Dwellings

The Three Facts of California’s ADU Boom

Accessory dwelling units (ADUs) in California are “a revolution in progress,” in the words of researchers at the University of California’s Center for Community Innovation. A series of laws enacted over the past five years have systematically eliminated most explicit and implicit legal barriers to ADU construction across the entire state. Using data reported to the California Department of Housing and Community Development, I investigated likely economic and regulatory determinants of ADU growth across California cities.