Current as of September 2025
What is an ADU?
An Accessory Dwelling Unit (ADU) is a smaller secondary home on the same lot as a primary dwelling. ADUs are independently habitable, containing permanent provisions for living, sleeping, cooking, sanitation, and heating.
ADUs may take one of the following forms within the City:
- Detached ADU—A stand-alone structure that is separate from the primary dwelling. This may include new construction or the conversion of an existing accessory structure such as a garage.
- Attached or Internal ADU—A unit created within or attached to the primary dwelling. Examples include basement or attic apartments, additions to an existing home, or units above a garage.
Note: ADUs in the City may be up to 900 square feet in size, consistent with state law and City code.
Why ADUs?
When adopting the ADU standards in 2018, the City’s intent was to:
- Create new rental housing units while respecting the look, scale, and feel of single-family development patterns;
- Offer housing choices with less average square footage and more efficient use of residential land;
- Provide flexible housing options to meet changing family needs, including multi-generational households and smaller or larger families;
- Support affordability by reducing overall housing costs and expanding rental opportunities;
- Offer additional housing options for seniors, persons with disabilities, veterans, and individuals with limited incomes;
- Contribute to statewide housing goals for increased supply, choice, and affordability.
ADU = ACCESSORY DWELLING UNIT
Are there restrictions on ADUs?
- Accessory to an existing dwelling: ADUs must be accessory to an existing dwelling. If the lot is vacant, the owner must first build a single-family dwelling or duplex before adding an ADU.
- Setbacks and height: ADUs must comply with standard setback and height requirements for the zone.
- Parking: Parking may be provided voluntarily but is not required.
- Utilities and System Development Charges (SDCs): ADUs must be connected to City water and sewer services. ADUs connected through the primary dwelling are not subject to additional SDCs for water or sewer. Transportation and park SDCs may apply consistent with City methodology and state law.
- Size: ADUs may be up to 900 square feet in size.
- Building code compliance: ADUs must comply with the Oregon Residential Specialty Code (ORSC). If the ADU is under 400 square feet, the Small Home Specialty Code (ORS 455.616) may apply.
- Owner occupancy: State law prohibits requiring either the primary dwelling or the ADU to be owner-occupied.
