Cottage Housing

Snohomish County first approached cottage housing as a new housing option in 2005. As part of the Urban Centers Demonstration Program, cottage housing was envisioned as a transitional density between larger scale developments and lower density residential areas. Regionally, cottage housing was increasingly becoming a popular housing type. Many local jurisdictions like Shoreline and Mill Creek had experienced success in realizing cottage housing communities in their own backyards. Snohomish County took cues from those successes in tailoring cottage housing practices to local conditions here.

As work began in 2006 on a broader set of design standards for residential development, the focus of cottage housing shifted away from urban centers and instead toward medium and low density residential areas. This led to regulations adopted in 2009, which allowed cottage housing in five residential zones and provided bulk requirements, design standards, and a new definition of cottage housing to the code.

Despite these efforts, the County has seen little interest in cottage housing. And to date, no cottage housing project has been proposed under the cottage housing regulations. Speculation as to why ranges from the Great Recession (2007-2012) to a condominium ownership requirement and low density bonus incentives and a niche housing market. Snohomish County is now casting a wide net to explore potential regulatory changes to the cottage housing code that could realize this housing type.  

What Cottage Housing Is

Cottage housing is a mildly dense, small scale housing form. Units are typically built at or below 1,200 square feet with modest dimensions. By design, cottage housing is geared toward single-family tenancy and can be constructed as either attached or detached units. The nature of cottage housing is one of community where shared space and semi-private space are favored over purely private space. Cottage housing developments are usually focused around community courtyards where housing clusters numbering four to twelve units open onto the shared space.

Cottage housing can provide an affordable alternative to larger single-family homes and suit the needs of many different household types. They're especially adept at serving smaller families, single individuals, the elderly, and those with mobility challenges.

These attributes are perhaps best represented in the collage below:

Aside from these examples, the County defines cottage housing in this way:

Cottage Housing Dwelling means a single-family detached dwelling unit constructed in groups of four to twelve units located on a commonly owned piece of property with each unit no larger than 1,200 square feet. The units are built around common open space, with minimal private yards. Units do not have individual garages; parking is located in separate areas or in structures on the periphery of the site in order to minimize space taken up by driveways.

How It's Regulated Now

Snohomish County cottage housing regulations are codified in SCC 30.41G. Those regulations are primarily designed to address site layout, amenities, building sizes and setbacks, and architectural features.

For instance, the cottage housing code sets out to design buildings that are built with an attractive and low profile. The maximum unit size tops out at 1,200 square feet with no more than 800 square feet of ground floor living space. Maximum height is set at a modest 18 feet (about 1.5 stories) unless dwelling units are provided with strongly pitched roofs for character, in which case the maximum height is increased to 25 feet (about 2 stories) if the roof pitch is 6:12 or steeper. To enhance connections to other spaces and buildings in a cottage housing community, covered porches and covered entries are required as a design element.

But it's not just about building form and size. Cottage housing regulations are also built around concepts of shared space and community. Cottage housing units are largely required to frame a shared courtyard at the center. Building fronts are encouraged to be oriented toward shared courtyard and all units must have access to and through that space. Semi-private space is also a welcome feature when it is placed between a shared courtyard and building fronts. The goal here is to keep the physical space from eye-level and above free from structural obstructions. It's that line of sight mixed with shared and semi-private spaces that builds a cohesive community, and that's reflected in the design of the cottage housing code. 

Cottage housing is limited to a handful of residential zones, including the following: R-9,600, R-8,400, R-7,200, T, and LDMR. As an incentive to build smaller dwelling units, the cottage housing code provides a density bonus of up to 1.2 times the underlying zoning maximum.

Project Scope

The project scope for cottage housing has been narrowed to focus on five primary policy areas (although stakeholder feedback may result in additional considerations): 

  • Amending the definition of cottage housing to allow this type of housing on fee-simple lots;
  • Adjusting the density bonus for cottage housing and exploring additional incentives;
  • Making additional amendments to the cottage housing regulations in response to stakeholder feedback and research of other jurisdictions;
  • Amending the definition of “drive aisle” to clarify their use in cottage housing developments which use the unit lot subdivision regulations; and
  • Amending unit lot subdivision sections in SCC 30.41A.205 and SCC 30.41B.205 so as to be consistent with changes to the cottage housing regulations, clarify that attached single-family dwellings are allowed in a townhouse unit lot subdivision, and allow the use of density bonuses in townhouse unit lot subdivisions.

Project Contact

David Killingstad, Principal Planner
425.388.3311 x2215

Project Schedule

Planning Commission Review
County Council Review

Project Documents