Best Adu in Portland, OR | AccessoryDwellingUnit Experts

Looking for best adu in Portland, OR? Call AccessoryDwellingUnit Experts for a contact a provider — no obligation. Licensed adu builders serve Portland and the surrounding area, and you'll get straight answers on timing and what affects the price.

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

A top-tier ADU balances aesthetic appeal with practical functionality, ensuring you get the most utility from your property. You need a high-performance build if you want to avoid future maintenance headaches and ensure your unit holds its value over time. We emphasize quality materials and expert craftsmanship to deliver a space that serves your family well for many years. Exact pricing confirmed free on the call.

Frequently asked in Portland

What are some accessory dwelling unit options near me in Portland?

What are prefab ADUs?

Prefab ADUs, or prefabricated accessory dwelling units, are built off-site in a factory and then transported and assembled on your property in Portland. This method can sometimes speed up the construction timeline and potentially reduce costs due to factory efficiencies. They come in various designs and sizes. Discussing prefab options with a pro can help determine if it's the right fit for you.

What accessory dwelling unit services are available?

What is an ADU estimate?

What does accessory dwelling unit mean?

Accessory dwelling unit (ADU) means a secondary, independent housing unit located on a single-family residential lot in Portland. It has its own kitchen, bathroom, and living space. ADUs can be detached structures like backyard cottages or integrated into the main home, such as basement or garage conversions. They provide flexible housing solutions for homeowners.

What is an ADU company?

What are accessory dwelling unit grants?

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

All cities in Oregon →

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

Service area details

630,498residents

4,723per sq mile

8ZIP codes served

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: Downtown Portland, Pearl District, Hawthorne District, Alberta Arts District, Sellwood-Moreland — and every surrounding area.