AccessoryDwellingUnitDirect ES 📞 (815) 860-2798

Cost to build accessory dwelling unit — Portland, OR

Looking for cost to build accessory dwelling unit in Portland, OR? Call AccessoryDwellingUnit Direct 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 involves variables that shift your total investment. The footprint size and complexity of the architectural design are primary factors. Are you planning a detached unit that requires new utility trenching, or is this a garage conversion that uses existing plumbing? Site accessibility, soil conditions, and your choice of finishes—like luxury flooring versus standard options—also play significant roles. Permitting fees vary widely depending on your local municipality and current zoning requirements. Exact pricing confirmed free on the call.

About this service

The expense of building an ADU varies based on site preparation, whether you need to run new sewer or electrical lines, and the level of interior customization you choose. Larger custom builds naturally require more materials and labor than simpler conversions. We provide exact pricing confirmed free on the call.

Frequently asked in Portland

What are the disadvantages of ADUs?

Some homeowners might find the initial construction costs for an ADU to be a barrier. Navigating local permitting processes, especially in a city like Portland, can also take time. There's also the consideration of how an ADU might impact your property's overall maintenance. However, the long-term benefits are often substantial.

How much does an ADU cost in Oregon?

The cost to build an ADU in Oregon, including Portland, varies widely based on size, features, and site complexity. Factors like foundation type, materials, and whether it's attached or detached significantly influence the price. Getting a personalized quote from a local expert is the best way to understand the investment for your Portland ADU.

What are the rules for ADUs in Oregon?

Oregon has state legislation that encourages ADUs, but cities like Portland have their own specific requirements. These often include regulations on lot size, density, setbacks, and parking. It's vital to consult Portland's Bureau of Development Services for the most current and accurate information for your specific location.

Is ADU allowed in Maryland?

Yes, ADUs are permitted in Maryland, and the state has been working to make them more accessible. Many counties and cities, including Baltimore, have implemented regulations that allow for the construction of accessory dwelling units. Homeowners should always verify local zoning laws for specifics.

What are the rules for ADU in California?

California has been at the forefront of ADU legislation, with state laws designed to simplify their construction. Cities must comply with these state mandates, though they can impose certain design standards. Understanding both state and local rules is important for any ADU project in California.

California has offered grant programs to help homeowners finance the construction of ADUs, making them a more attainable option. These grants are intended to lower the financial barrier to entry for ADU projects. It's advisable to check for current availability and eligibility requirements for these California ADU 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: Pearl District, Hawthorne, Alberta Arts District, Sellwood-Moreland, Mississippi Avenue — and every surrounding area.

Areas we serve

Browse by state, then city.

Alabama (4)
Alaska (1)
Arizona (8)
Arkansas (1)
California (29)
Colorado (4)
District of Columbia (1)
Florida (9)
Georgia (3)
Hawaii (1)
Idaho (1)
Illinois (2)
Indiana (2)
Iowa (1)
Kansas (2)
Kentucky (2)
Louisiana (3)
Maryland (1)
Massachusetts (1)
Michigan (2)
Minnesota (2)
Missouri (3)
Nebraska (2)
Nevada (4)
New Jersey (1)
New Mexico (1)
New York (4)
North Carolina (7)
Ohio (4)
Oklahoma (2)
Oregon (3)
Pennsylvania (2)
Rhode Island (1)
South Dakota (1)
Tennessee (5)
Texas (13)
Utah (1)
Virginia (4)
Washington (4)
Wisconsin (2)