The legal issues in 'backyard cottages'

The state directs such small accessory units, to increase housing in cities. But cities get to regulate the local conditions. The fight in Seattle is joined in a few weeks.
The state directs such small accessory units, to increase housing in cities. But cities get to regulate the local conditions. The fight in Seattle is joined in a few weeks.

'ꀜBackyard cottages'ꀝ are likely to be one of the last land-use legacies of the Nickels regime. Some will question whether these small dwelling units on lots with existing homes are legal, but let's be clear: Allowance of such "mother-in-law" dwellings is not a question of legality, since state law mandates cities to provide for accessory dwelling units (ADU's) in local land use codes. But there are plenty of policy questions and political hot buttons.

Legally, accessory dwelling units (ADU's) have been required in Washington since the early 1990s, and Seattle first allowed attached ADU's in 1994. Where it gets contentious is the provision giving municipal discretion in how to apply the concept.

Some neighborhood advocates such as Crosscut writer Kent Kammerer have suggested that the backyard cottage proposal is a de facto rezoning of single-family neighborhoods, somehow placing the cottages out of sync with underlying land use law. However, this contention ignores the state mandate for ADU'ꀙs, and deflects attention from the real issue, which is a policy choice about the circumstances under which accessory dwelling units (ADU'ꀙs) should be allowed.

Backyard cottages have been allowed on a limited basis within an area of southeast Seattle since 2006. According to proponents, such cottages are now ready for prime time as a nod to sustainability and enhanced efforts to provide a range of housing types to residents. Backyard cottages citywide would show an evolution of perceived 'ꀜlocal circumstances'ꀝ in Seattle that move "mother-in-law dwellings" across the yard rather than keep them indoors.

Interest in ADU'ꀙs grew in the 1980s and 1990s in the wake of changing demographics and concerns about housing availability and affordability. In 1990 and 1991, the state's Growth Management Act (GMA) mandated attention to housing needs and encouraged innovative land use techniques to enhance opportunities for affordable housing. The 1993 Housing Policy Act directed cities planning under GMA to adopt ordinances by the end of 1994 that incorporated accessory dwelling provisions within land use codes, 'ꀜsubject to such regulations, conditions, procedures, and limitations as determined by the local legislative authority.'ꀝ

ADU ordinances typically govern a range of relevant issues pursuant to 'ꀜlocal circumstances,'ꀝ ranging from size, number of occupants to parking and design criteria. From the beginning, some cities kept ADU'ꀙs inside then-existing housing stock rather than new construction detached from the existing home. Others, like Seattle, limited ADU'ꀙs to dwelling actually attached to residences, until 2006 when the experimental program with detached accessory dwelling units (or DADUs) began in Southeast Seattle.

Unlike Seattle, many other cities in the Puget Sound region such as Clyde Hill, Issaquah, Kirkland, Mercer Island, Shoreline, Newcastle, Redmond, parts of unincorporated King County, Woodinville, and Yarrow Point have permitted detached ADU'ꀙs for some time. Nationally, the concept is familiar, and well received. A recent U.S. Department of Housing and Urban Development case study touts "by right" attached and detached ADU's in Lexington, Massachusetts, a successful ordinance and development program in Santa Cruz, California, and Portland's relaxed approach which allows DADU's in all development zones.

The backyard cottage issue typically raises issues of visual impact and neighborhood character. Usually, permitting schemes favor larger lots to assure attention to setbacks. The current ordinance proposal in Seattle — and its careful marketing by Department of Planning and Development staffers — shows lots of fine tuning of these impact issues with predictable attention to height, bulk, and setbacks.

From a legal perspective, fine tuning cottages to appropriate lots, settings, and ownership schemes is a defensible reflection of policy choice. Up to a point. The City Council will be more subject to court scrutiny if it ventures over the line into politically-driven, arbitrary limits to the cottage permit pipeline (such as the currently proposed 50 DADUs per year). The same would be true if Seattle emulates some other cities by enacting hoop-jumping ordinance provisions that — permitted in theory but impossible to build in practice.


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About the Authors & Contributors

Chuck Wolfe

Chuck Wolfe

Chuck Wolfe provides a unique perspective about cities as a London-based urbanist writer, photographer, land use consultant and former Seattle land use and environmental attorney.