ADU legislation can move forward after clearing appeal

After several months in an appeals process, laws to reform accessory dwelling units (ADUs), like mother-in-law apartments and backyard cottages, will be considered by the Seattle City Council. The idea is to allow more ADUs, perhaps two per lot, and to make them less onerous to build, increasing housing affordability options in single-family zones.

Back in October, the city released its final study of the impacts of a law change, but the findings had been appealed by the Queen Anne Community Council (QACC)—led by Marty Kaplan, a longtime opponent of backyard cottage reform. (The same group was successful in appealing an earlier impact study in 2016.)

Monday, a hearing examiner ruled the city’s study was sufficient to move forward, clearing ADU reform, which has been in the works since 2014, to move forward.

While the appeal meant the Seattle City Council couldn’t pass legislation, the councilmembers have been preparing to fine-tune the legislation, including parking requirements, floor-area ratio limits, and owner occupancy requirements.

For example: While currently, a homeowner would have to include a sometimes-expensive and often-intrusive parking spot with every ADU built on the property, the city could remove the parking requirement, or only require parking on a second ADU.

Owner-occupancy—the idea that to rent an ADU, the owner of the property must be living on it, too—could also go a couple of ways. Currently, a homeowner has to live on the property in order to rent out an ADU. In the city’s preferred alternative from its October study, the owner-occupancy requirement is eliminated for the first ADU, but a minimum of one year of continuous ownership would be required for a second ADU.

The concern, City Councilmember Mike O’Brien told us in early May, was that “developers will come in and tear down single family homes and build more new homes in backyard cottages.”

“What the analysis showed was, no, that’s not actually going to happen,” said O’Brien. “It’s not a viable economic model ... but we are seeing a lot of developers tear down single family homes, and what they build is a bigger single family homes. And if we want to encourage folks to not do that and instead maintain existing family homes and build backyard cottages or in-law units.”

While the QACC called the legislation an “upzone” (presumably a nod to a separate issue of zoning changes to increase density throughout the city) buildings could get a little smaller as part of the effort. O’Brien has introduced companion legislation could reduce the floor-area ratio requirements—how much square footage a house can have in relation to its lot—for all single-family homes.

Single-family zoning in Seattle is currently extremely permissive. While it has height limits (25 to 30 feet), there’s no limit to floor-area ratio (FAR)—that is, the size of the home in relation to the lot—as long as the giant home that results is only one home. Under the legislation, single-family zones could get a FAR limit of .5, so, for example, a single-story house could only have a footprint of half the lot. O’Brien said the council plans to carve out some small exemptions for additions or planned remodels to existing houses, although, since ADUs wouldn’t be included in the FAR limit, homeowners could build in a mother-in-law unit to get around them.

The major idea behind ADU reform is around affordability: ADU reform was among the recommendations of the Housing Affordability and Livability committee (HALA) in 2015, although reforms have been underway since 2014.

The Seattle City Council Sustainability and Transportation Committee—not typically the committee for zoning, but since O’Brien’s been managing the effort for a while, it’s in his committee—is having a special meeting on Wednesday, May 29 for a briefing and discussion on the proposed legislation, and then another public hearing June 11. The committee will be discussing amendments, and possibly voting on amendments, June 18.

If the legislation moves through the committee process quickly, it could be voted on by the whole Seattle City Council by the end of June.