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Attached ADU in Washington
Renovate Builders
4555 39th Avenue Southwest, Seattle, WA 98116Adair Homes
4400 Northeast 77th Avenue, Vancouver, WA 98662Adair 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
Alta Casa
5123 Northeast 94th Avenue, Vancouver, WA 98662Alta Casa Remodeling is a Vancouver, WA ADU builder specializing in accessory dwelling units, garage conversions, in-law suites, and home additions. They also offer kitchen, bathroom, and full home remodels, backed by a one-year workmanship warran... read more
Northwest Builders & Renovation
1135 Lake Washington Boulevard North, Renton, WA 98057Lindal Homes
6840 Fort Dent Way, Seattle, WA 98188Lindal Homes offers custom ADU and DADU kit home solutions across the US and Canada. Flexible floor plans, the Lindal Elements collection, and system-built construction make adding a backyard cottage or guest suite efficient and cost-effective.read more
Home Care Contractors
10634 East Riverside Drive, Bothell, WA 98011Home Care Contractors builds ADUs in King County, including DADUs, garage conversions, and basement units. They handle permits, design, and construction. Costs range from $300K–$700K, with timelines of 7–13 months total.
read moreTiny Cottage Builders NW
26650 Ice Harbor Drive, Burbank, WA 99323Tiny Cottage Builders NW offers ADU construction, garage conversions, basement finishing & home remodeling in Tri-Cities, WA. Led by Brandon Lott, every project is personally managed ensuring quality craftsmanship & clear communication.read more
Deane Home Services
17837 1st Avenue South, Normandy Park, WA 98148Deane Home Services builds ADUs in South King County, WA, including garage conversions, basement remodels, and detached backyard cottages. Licensed, bonded & insured. Serving Kent, Renton, Federal Way & more.
read moreMicrohouse
114 North 42nd Street, Seattle, WA 98103Microhouse is a Seattle-based ADU builder specializing in custom detached ADUs (DADUs). They guide homeowners through zoning, design, and construction. Seattle permitted 551 DADUs in 2022, with a 40% increase in 2023. Microhouse offers site assess... read more
Bellingham ADU Builders
2111 King Street, Bellingham, WA 98225Bellingham ADU Builders offers full-service ADU construction in Whatcom County, including detached and attached ADUs. Costs range from $200K–$550K+. Permits included. Free 48-hour feasibility study available. HB 1337 allows up to two ADUs per lo... read more
New Day Construction
15021 116th Place Northeast, Kirkland, WA 98034New Day Construction is a licensed ADU builder in Bellevue, WA, with 21+ years of experience and 250+ projects. They build detached, attached, garage, basement, and custom ADUs, managing permits and design from start to finish.
read moreBlue Lake Construction
12721 Northeast Bel Red Road, Bellevue, WA 98005Neil Kelly Washington
804 North Alberta Street, Seattle, WA 97217Neil Kelly Washington offers ADU design and build services in the Northwest, including detached ADUs, garage conversions, and attached units. Their team navigates local permits, balances design with functionality, and helps homeowners add value th... read more
Coates Design Architects
900 Winslow Way East, Bainbridge Island, WA 98110Seattle ADUs offer rental income & flexible living. Coates Design Architects guides homeowners through detached, attached, garage & basement conversions. Costs range $200K–$350K+, with 7–11 month timelines. Sustainable design & per... read more
Other cities in Washington
- Bainbridge Island
- Battle Ground
- Bellevue
- Bellingham
- Black Diamond
- Bothell
- Bremerton
- Buckley
- Burbank
- Camas
- Edmonds
- Everett
- Fall City
- Federal Way
- Goldendale
What you need to know
Searching for top Attached ADU ADU Contractors in Washington? Our directory highlights trusted local professionals who specialize in designing and building accessory dwelling units (ADUs).
Working with a qualified Attached ADU ADU Contractor in Washington ensures your ADU project meets local building codes, zoning laws, and permit requirements. Whether you're planning a detached ADU, garage conversion, or backyard cottage, experienced Attached ADU professionals can guide you through every step.
Washington homeowners are increasingly investing in ADUs to create additional living space, generate rental income, or support multigenerational living. The Attached ADU experts featured here bring local expertise and proven experience to help make your project a success.
Browse our listings to find the best Attached ADU ADU Contractors in Washington, and get started today.