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ADU types we build in Seattle

Five ADU types for Seattle lots, each with design, SDCI permits and construction.

Check what my lot allows

Small white cabin with a blue metal roof among evergreen trees

Choose a starting point

Small blue backyard cottage with a covered porch

Backyard cottage (DADU)

A detached ADU in the back yard, often off the alley.

Backyard cottage (DADU)

Garage converted with French doors and a window, car parked in front

Garage conversion

Turn a garage into a legal, livable unit.

Garage conversion

Small bungalow with a covered porch and a lawn

Attached ADU

An addition joined to your house with its own entrance.

Attached ADU

Living room with a fireplace, plants and an orange pendant lamp

In-home ADU

A unit inside your house: basement, wing or upper floor.

In-home ADU

Floor plan drawing with symmetrical rooms on pale green paper

Design and permits

Plans, engineering and the city review, handled for you.

Design and permits

Which ADU type fits my lot?

A back yard with alley access suits a cottage. A tall basement suits an attached ADU. A detached garage can be converted. Many owners do two: a basement unit now and a cottage later.

Compare costs

Is your lot ready for an ADU?

Send your address and a sentence about what you want. We look up the zoning, setbacks and utility routes and reply with the ADU types that fit.

We build in Seattle, WA.