Six years ago, facing one of the nation’s worst housing shortages, California lawmakers tried an experiment: They passed a series of laws making it easier for homeowners to construct a second, smaller home on their property — an accessory dwelling unit, in the parlance of housing policy.
This move did not end California’s housing crisis on its own. But in just a few years developers there have built tens of thousands of in-law apartments and granny flats, putting a real dent, advocates say, in the state’s housing shortage.
In Massachusetts, a state wrestling with a deep housing crisis of its own, legislators have not been nearly as decisive. Time and again, efforts to legalize ADUs statewide have fizzled on Beacon Hill, most recently last week, when a promising amendment died with the economic development bill. That leaves regulations up to cities and towns, creating a patchwork of local rules that developers say is nearly impossible to navigate at scale.
In most towns that have legalized ADUs in some capacity — as of 2018 there were 68 in Greater Boston that allowed them, and a number of others have legalized them since — only a handful of units are permitted each year. Many places still ban them outright.
The tension between statewide rules and local control of zoning is a constant in Massachusetts housing policy, and towns often push back on mandates from Beacon Hill. But housing advocates worry that if the state can’t even craft policy for something as modest as a backyard cottage, it will never tackle the bigger challenges.