Anthony Flint is a fellow at the Lincoln Institute of Land Policy, a think tank in Cambridge, Massachusetts. He is the author of Modern Man: The Life of Le Corbusier, Architect of Tomorrow and Wrestling with Moses: How Jane Jacobs Took On New York's Master Builder and Transformed the American City.
Relaxing rules on “Accessory Dwelling Units” drastically increased affordable housing stock in the small city of Durango.
Planners call them Accessory Dwelling Units—plus the inevitable acronym, ADUs. What they mean are the granny flats and in-law apartments sprinkled throughout cities and towns across the land, the finished basements, above-garage studios, rehabbed carriage houses, and other outbuildings on parcels generally zoned for single-family homes.
But here’s what they really are: an instant source of affordable housing, if only they could be freed from extensive restrictions that cities and towns have in place that tightly limit who can live there.
When I was at the Office for Commonwealth Development under Massachusetts Governor Mitt Romney, we tried to increase the supply of new multi-family housing at smart growth locations, in town centers or by transit stations. Yet it quickly became apparent that there were thousands of existing homes already, in the form of Accessory Dwelling Units. The trick was just to open them up.
This was no small task, as it turned out. Fueled by NIMBYism and concerns about density and school enrollment and parking and congestion, cities and towns wrote reams of codes requiring that property owners prove any occupants of ADUs were actually related. If not, owners could expect to be visited by inspectors checking out separate entrances and working kitchens and evidence of occupation, and brace for a fine. Eagle-eyed neighbors spotting a second mailbox or satellite dish were more than happy to alert the authorities.
In the face of this kind of code paralysis and regulatory over-reach, it’s understandable that reformers would just give up, and try to change policy in other ways. But in recent years, a sensible program of disentanglement has emerged from an unlikely place—the small city of Durango, Colorado, just north of the New Mexico border.
Conjured in the era of railways and mining, Durango has become a visitor destination, close to national parks, monuments, and forests, the Mesa Verde cliff-dwellers World Heritage Site, skiing, mountain biking, and whitewater rafting. It doesn’t quite have the affordability problem of Aspen or Telluride, but housing is a major issue for the array of incomes in the population of nearly 17,000.
From 2009 to 2013, confronting development pressures and concerned about housing, Durango overhauled its Land Use and Development Code, which called out Accessory Dwelling Units as an acceptable component of housing stock. A predictable process with reasonable standards was put in place for building new ADUs: a limit on the number of occupants (no more than five unrelated people), rules about how small the living space could be (550 square feet), an owner-occupied home requirement (no absentee landlords renting out both the home and the ADU), a ban on short-term vacation rentals such as through Airbnb, and design guidelines for balconies, window placements, and exterior staircases.
The big problem, however, was what to do with existing ADUs.
Since many of these homes were technically illegal, a form of “ADU Amnesty” was launched. Starting with two neighborhoods as a pilot program, the city asked owners to come forward about ADUs on their property. Residents could fess up in three categories—pre-1941, when there were essentially no rules about ADUs; 1941 to 1989, when ADUs could be considered legal but non-conforming use; and 1989 to the present, when tighter zoning was in place.
If somebody established an ADU completely under the radar, they were asked to pay the fee they were supposed to pay, ranging from $2,000 to $9,000, and the property got logged into the city’s inventory database. Owners signed affidavits on basic structural safety, and filled out forms on the number of occupants, age of the structure, and the utilities in place, and furnished a photo.
Getting the transactional details on the record was basically a process of regularizing what was a robust informal economy. And with the existing ADUs thus inventoried, and the rules in place for new ADUs, the city was all set, right? Not exactly. Opposition was fierce, and clever.
Rebellion in the pilot neighborhoods organized as CHEN: Citizens for Healthy Established Neighborhoods, which churned out letters to editors, op-ed essays, and leaflets with a red slash across “ADU.” The question was posed: affordable housing, or slums? One resident mapped her neighborhood and came up with hundreds of units already there, and hundreds more that would be enabled. That didn’t take long to make the front page.
City Hall and the planning office got mercilessly picketed, and somebody placed an ad in the local newspaper touting free building lots—listing the telephone number of the planning office as the place to call for more information.
The planners held firm, making a few minor adjustments, but not compromising on the basic principles of the program. They also launched a public education campaign, producing a video, Know Your ADUs. Amid the dark talk about slums, they kept it light and accessible—even fun, to the extent that was possible, what with lexicon like “legal non-conforming use” being part of the conversation.
The leaders of the effort, the planners Vicki Vandegrift and Scott Shine, shared a game at their presentation at the American Planning Association National Planning Conference last month in Phoenix. Yes, it was time to play “Unit or Not a Unit?”—a series of photographs that demonstrated how some single-family homes look like ADUs, while many ADUs are attractively woven into the urban fabric. (As the quiz went along, we all got better at spotting the dead giveaways—double meters and two street numbers, for instance).
One thing is certain, and that’s the number of communities across the nation confronting this very same issue. The APA session, theatrically titled Accessory Dwelling Units: The Durango Experience, was packed. A long line formed at the microphone for questions. Granny flats and in-law apartments are rising to the top of the affordability conversation from Boston to Seattle.
There may be no secret sauce for getting this done, but demonstrating the benefits—to owners, and to the community at large—is surely a centerpiece. Planners need to be flexible, but not compromise. And above all, stay positive. Even if they’re forced to change their telephone numbers.