Adu building — Portland, OR

Last updated: September 24, 2026

What affects the price

Building an ADU is a major project, and the final bill depends on a few key things. Site prep is a big factor; if your land is sloped or needs extensive utility connections, costs go up. The materials you choose—from siding to kitchen finishes—also change the math significantly. Whether you’re building a detached unit or converting an existing garage shifts the permit requirements and structural work needed. We provide exact pricing confirmed free on the call.

About this service

Building an ADU involves taking a project from initial design through site preparation, framing, and final inspections. You need this service when you are ready to expand your property’s utility. Costs depend on whether you are building a custom structure or converting existing space, as well as local permit fees. Exact pricing confirmed free on the call.

Frequently asked in Portland

Also serving nearby: Vancouver · Beaverton · Gresham · Hillsboro · Salem

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More on this: HUD ADU resources — ADU policy and financing research.

Service area details

Serving all of Portland — population 630,498; about 4,723 residents per square mile across 133.5 sq mi. ZIP codes covered include 97201, 97202, 97203, 97204, 97205, 97206, 97207, 97208.

Neighborhoods served in Portland: Pearl District, Hawthorne, Sellwood-Moreland, Hollywood District, Alberta Arts District, Mississippi Avenue — and every surrounding area.