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November 2018

Builders urge support for more backyard cottages to help ease housing shortages

Backyard cottages can help alleviate housing shortages while providing an affordable option for various segments of the population. Nevertheless, efforts to create "living small" opportunities are stymied for myriad reasons, according to the Master Builders Association of King and Snohomish Counties (MBAKS).

MBAKS, the nation's oldest and largest local homebuilders association, released a white paper outlining benefits and hurdles associated with cottage housing. The report included a synopsis of regulations in 16 jurisdictions around its two-county service area. It reveals the region has wide-ranging regulations that allow (or forbid) backyard cottages.

Cottage housing encompasses Accessory Dwelling Units (ADU), Detached Accessory Dwelling Units (DADU), or "mother-in-law" suites for purposes of the Master Builders' advocacy.

"Cottages provide additional housing units that are compatible with the look and scale of single-dwelling development, make  more efficient use of existing housing stock and infrastructure, and provide a mix of housing options," the authors of the white paper stated. Proponents also cite energy efficiency and fewer maintenance and cleaning requirements as plusses.

MBAKS also noted such homes can be built to reduce to reduce the environmental impact by using green construction techniques, by creating more walkable neighborhoods and in other ways. Its Built GreenĀ® rating system has certified two projects in the past few years, "and would love to do more."

The builders' white paper also cites various benefits and barriers reported by the association's member-developers:

Makes is easier for younger buyers to qualify (renting out an ADU provides additional income)Lengthy bureaucratic process to obtain permits
Enables seniors to age in place (ADUs can house a caregiver or be rented as a new revenue stream)Extensive and expensive with codes
Expands options for multigenerational livingAdded tax burden
Can be greenExcessive restrictions and red tape

Size restrictions

MBAKS indicated an estimated 75 percent of what looks and functions like cottage housing in Seattle are, in fact, non-permitted ADUs. Many homeowners do not legally permit their backyard cottages due to onerous regulations.

Seattle's restrictions for DADU include:

  • Maximum size of 800 sq. ft.
  • Must have a dedicated off-street parking spot
  • The property owner must occupy either the home or the backyard cottage as a permanent and main residence for more than 6 months out of the year
  • Entrance placement restrictions

Home builders believe cottage housing can be increased using various approaches, including:

  • Removing owner occupancy requirements
  • Waiving permit and impact fees
  • Flexibility in maximum floor area requirements or lot area coverage
  • Relaxing setback requirements
  • Reducing off-street parking requirements

Founded in 1909, the Bellevue-based MBAKS has nearly 3,000 member companies. In addition to homebuilders, its membership includes architects, remodelers, suppliers, manufacturers, plus sales and marketing professionals.