ADU Craft Portland

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Where we build ADUs around Portland

Oregon sets the statewide floor for ADUs; each city decides the details. Here is what shifts as you cross city lines.

What should Portland homeowners know before building an ADU?

As of October 2026, Portland's ADU rules sit in Zoning Code Chapter 33.205, largely reshaped by the Residential Infill Project. Points that come up on almost every lot:

  • Two units. Many house lots can carry two ADUs, but only one may be attached to the house.
  • Size. 800 sq ft or 75% of the house's living area, whichever is smaller, with an exception for basements in houses at least five years old.
  • Parking. No extra on-site parking is required for an ADU.
  • Fees. The city waives system development charges for ADUs whose owners sign a 10-year covenant against short-term rental.

See our SDC waiver guide and our size guide.

Single-family home

Which nearby cities do we serve?

Beaverton

Washington County's west-side suburb. State law sets the floor, and we confirm the current city standards for your lot before design.

ADUs in Beaverton

Lake Oswego

A lakeside city that allows one ADU with a single-family house, up to 800 sq ft of gross floor area, with rules on where an entrance can go.

ADUs in Lake Oswego

Milwaukie

A Clackamas County city that removed owner-occupancy and parking rules for ADUs effective January 1, 2020.

ADUs in Milwaukie

Gresham

East Multnomah County. ADUs up to 900 sq ft or 75% of the house, a Type I review, and no short-term rentals.

ADUs in Gresham

Check what your lot allows

Send us your address and a line about your plans. We look up the zoning, lot size and overlays, then tell you which ADU types are realistic.

Serving Portland, Beaverton, Lake Oswego, Milwaukie and Gresham.