Keyser Construction Inc is a Portland, OR ADU contractor since 1996. They build detached cottages, garage conversions, basement & attic ADUs. Licensed, bonded & insured, offering free estimates and permit handling across the Portland metro... read more
As a premier ADU contractor in Portland, Sert Construction specializes in designing and building high-quality, functional ADUs. Whether you're considering an added space for rental income, additional family space, or a home office, their team of e... read more
Adair Homes offers custom ADU builder solutions, including stand-alone and attached accessory dwelling units. With a six-step building process, financing via Basis Home Loans, and expert guidance, Adair simplifies new home and ADU construction.read more
Tweto Architecture specializes in ADU design, including detached ADUs, garage conversions & basement units. Serving Portland, Vancouver & Bend, they help homeowners add rental units, in-law suites & backyard cottages while navigating l... read more
Highland Ridge Remodeling helps Portland homeowners build accessory dwelling units (ADUs), including detached ADUs, garage conversions, and in-law suites. From design to permitting and construction, they deliver tailored, high-quality living space... read more
SLS Custom Homes and Remodeling is a licensed general contractor in Tigard, Oregon, serving Portland metro since 1983. Services include custom home building, kitchen and bathroom remodeling, room additions, and ADU construction.
read more
RTA Stone is a licensed remodeling contractor in Vancouver, WA, serving Washington & Oregon. Services include kitchen remodels, bathroom renovations, ADUs, additions & exteriors. Fixed-price quotes, 10-year warranty & dedicated project... read more
Shelter Solutions, Portland's trusted ADU builder since 1997, has completed 250+ accessory dwelling units. Offering full design-build services—from permits to occupancy—they specialize in custom detached ADUs, backyard cottages, and in-law sui... read more
Triangle Bar Group is a Portland, Oregon design-build contractor specializing in custom homes, additions, remodels, and ADUs. They manage design, permitting, and construction under one roof, serving Portland and Vancouver, WA homeowners.
read more
Integrity Timber Frame offers custom prefabricated timber frame home, cabin, and ADU kits in South Dakota. Using their TruFit™ System and SIPs panels, they deliver strong, energy-efficient, sustainable structures with faster assembly and potenti... read more
Jack Barnes Architect, PC is a licensed architectural firm in Portland, OR, specializing in residential design including ADUs, garage conversions, JADUs, and backyard cottages. Located on SE Belmont Street, they help clients navigate permitting an... read more
Conrad Construction is Portland's trusted ADU builder with 20+ years of experience. Specializing in backyard cottages, garage conversions, granny flats & detached ADUs, they handle permits, design & construction to boost property value.read more
Environs is a woman-owned design-build firm in Portland, Oregon, specializing in ADUs, home additions, remodels, and new construction. Licensed Oregon contractor (CCB 188377) with availability for projects breaking ground summer 2026.
read more
Jenson Contracting builds ADUs in Beaverton, Oregon, including detached ADUs, garage conversions & in-law suites. They navigate local size, height, setback & lot coverage rules to ensure compliant, self-contained accessory dwelling units.<... read more
Arciform is a Portland-based ADU design/build firm specializing in accessory dwelling units, including garage conversions, detached ADUs & in-law suites. They handle permits, historic properties & full construction.
read morePortland, Oregon has long been recognized as one of the most ADU-friendly cities in the United States. Since 2010, the city has waived System Development Charges (SDCs) for ADUs attached to or detached from single-family homes, significantly reducing construction costs for homeowners. This forward-thinking approach has made Portland a national model for urban density and housing affordability. Working with experienced ADU contractors in Portland is essential to navigating the city's unique permitting landscape and maximizing the potential of your property.
Portland allows ADUs in most residential zones, including R1, R2, R2.5, R3, R5, and R7 zones. However, building an ADU in Portland requires careful attention to local codes enforced by the Portland Bureau of Development Services (BDS). Key regulations include:
Hiring a qualified ADU contractor in Portland, Oregon means partnering with a professional who understands the city's specific permitting process, design standards, and construction requirements. A skilled contractor will handle everything from initial site assessment and architectural design to permit applications through the BDS and final construction. Portland's older housing stock — much of it built before 1950 — often presents unique structural and utility challenges that experienced local contractors are well-equipped to address.
Portland ADU contractors commonly build several types of accessory dwelling units to suit different property layouts and homeowner goals:
When selecting an ADU contractor in Portland, OR, look for professionals who are licensed with the Oregon Construction Contractors Board (CCB), carry proper liability insurance, and have a proven portfolio of completed ADU projects in the Portland metro area. Local expertise matters — a contractor familiar with Portland neighborhoods like Sellwood, Hawthorne, or St. Johns will better understand soil conditions, neighborhood design guidelines, and utility connection requirements specific to those areas.