Looking for the best custom ADU builders in Portland, Oregon? Our directory features 6 vetted custom adu builders serving the Portland area. Whether you're planning a new ADU construction, garage conversion, or backyard cottage, find the right builder for your project.
Since 1997, we have built 250+ ADUs in the Portland Metro area for people who want to age in place, keep family close, earn rental income, have a: guest house, home office, entertainment space, studio, home gym...
Specializing in ADU construction and related services in Portland, OR.
Specializing in ADU construction and related services in Portland, OR.
Specializing in ADU construction and related services in Portland, OR.
MyADU builds custom backyard homes that keep loved ones close—while giving everyone the space they need.
The Powell Group is a hands-on homebuilding company that specializes in the construction of custom homes and Accessory Dwelling Units (ADUs) in the greater Portland metropolitan area.
Portland is one of the top markets for accessory dwelling units in Oregon. With growing demand for affordable housing, ADU construction in Portland offers homeowners an excellent opportunity to add living space, generate rental income, or house family members. Our curated list of custom adu builders in Portland helps you find experienced professionals who understand local building codes, zoning regulations, and permit requirements.
ADU construction costs in Portland typically range from $150,000 to $350,000 depending on size, design, and finishes. Garage conversions are generally less expensive ($80,000–$150,000), while custom-built detached ADUs can cost more. Get free quotes from our listed custom adu builders to compare prices.
Yes, ADU construction in Portland requires building permits. Oregon has specific ADU regulations, and local zoning laws may have additional requirements. Our listed builders can help you navigate the permitting process.
ADU construction timelines in Portland typically range from 4–12 months, depending on the project type. Prefab ADUs can be installed in 2–4 months, while custom builds may take 8–12 months including design and permitting.