SNOHOMISH — The city’s planning commission last week determined a few key details as it is revising Snohomish’s code for Accessory Dwelling Units (ADUs) to meet updated state laws.
Some principles hashed out last week, voted by majority rule at the commission, were to:
• Set the maximum allowed size of an ADU to 1,000 square feet — a 5-2 vote. Other options were a little larger. The state law is
setting the minimum ADU size at 1,000 square feet.
• On detached ADUs, charge utility hookup fees upfront at the time of the build, with some stipulations — a 4-3 vote.
• Set park impact fees and traffic impact fees to be charged at 50% of the rate of the standard for the main property — a 4-2 vote.
• Require that one off-street parking stall is available for each ADU — a 4-3 vote. Some homeowners could point to their driveway and say they have enough parking spaces to satisfy the rule.
ADUs are small, separate living quarters on a property with their own sleeping quarters, kitchen and bathroom. They’re either add-on spaces to the main house, or usually a separate freestanding small house in the backyard called a detached ADU (D-ADU).
State rule changes the Legislature set in 2023 to encourage more housing options through ADUs are making Snohomish modify its rulebook. The state law requires cities of Snohomish’s size to allow up to two ADUs per residential lot. It must adjust its laws by mid-2025.
For a size comparison of 1,000 square feet, a single-wide mobile home can range from 500 to 1,300 square feet in floor plan, according to the Manufactured Housing Institute.
A size of 1,000 square feet should be adequate to fit three bedrooms and a bathroom, said Commissioner Gordon Cole, whose career is in constructing buildings.
Snohomish’s ADUs can be two stories tall, and stand up to 30 feet high in the code.
One of the commission’s biggest discussion points was whether to charge water and sewer hook-up fees for ADUs. Public works proposed ADUs get charged 50% of the usual fees. The standard fees to “drop-in” a 5/8ths meter for water and sewer in Snohomish total $23,090.
A majority of commissioners voted to require all detached ADUs get separate hook ups and pay the fees.
An alternative option was having the main property fully responsible for the water bills.
State law says the city can no longer require the owner to live on the same property as an ADU, though, meaning the main house and the ADU could both be long-term rentals. Public Works Director Nova Heaton noted things can get messy if the utility bill goes unpaid.
One caveat to the state’s owner-occupancy rule revolves around short-stay rental platforms such as Airbnb or Vrbo; in those cases, the property owner must live on the property.
Commissioners generally agreed with discounting impact fees for ADUs. If the city is serious about an affordable housing crisis, ADUs are a gentle way to add more affordable housing, commissioner Merritt Weese said.
Another public hearing is expected in June. The commission regularly meets on the first Wednesday of each month at 6 p.m. at the Snohomish Carnegie Building.
The planning commission’s eventual recommendation will be built into guidelines for the City Council for review.
Includes material from past Tribune reporting.
