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Attached ADU in Washington
Signature ADU
La Center, WA 98629Signature ADU is an experienced ADU builder offering full-service design and construction. Their team includes experts in architecture, general contracting, and project management, handling detached ADUs, garage conversions, granny flats, and in-law suites from start to finish.
read moreCascadia ADU
901 1st Street, Snohomish, WA 98290Cascadia ADU builds attached, detached, garage & basement ADUs across King, Snohomish, Skagit & Chelan Counties, WA. Full-service design, permitting & construction completed in 8–10 weeks with 10+ years experience.
read moreBackyard ADU
4813 37th Avenue Northeast, Seattle, WA 98105Backyard ADU is a full-service ADU contractor managing every stage of accessory dwelling unit builds, including feasibility, permits, site surveys, foundations, construction, utility connections, and condo legal services.
read moreNorth West Builders & Renovations
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 moreBlue Lake Construction
12721 Northeast Bel Red Road, Bellevue, WA 98005HiLine Homes
11306 62nd Avenue East, Puyallup, WA 98373HiLine Homes is an experienced ADU builder in Idaho with nearly 30 years in custom home construction. They offer attached and detached ADU designs for rental income, multigenerational living, or home offices, with financing options available.
read moreDrew Thatcher Construction
23 Country Club Drive Southwest, Lakewood, WA 98498Drew Thatcher Construction builds ADUs in Lakewood, WA, including detached units, attached ADUs, and garage conversions. Founded by a Navy nuclear engineer, they offer design-build services with local Pierce County expertise.
read moreHaas Development & Construction
4001 Aurora Avenue North, Seattle, WA 98103Haas Development & Construction offers ADU & DADU construction in Greater Seattle. They handle planning, permits, design, and builds for attached & detached units, including prefab DADU plans, helping homeowners add rental income or family housing.
read morePelletier Construction Group
1150 North 84th Street, Seattle, WA 98103Greater Seattle Remodeling
1850 130th Ave NE #1, Bellevue, WA 98005Greater Seattle Remodeling builds code-compliant ADUs across the Seattle metro, including detached ADUs, garage conversions, and basement apartments. They match homeowners with vetted contractors for permits, design, and construction.
read moreExceptional Home Builders Seattle
1525 11th Avenue, Seattle, WA 98122Exceptional Home Builders is a Seattle ADU contractor with 20+ years of experience. They offer full-service ADU construction, design-build, permitting, interior design, and renovations for backyard cottages, garage conversions, and basement units.
read moreDoyle Construction
300 Deschutes Way Southwest, Tumwater, WA 98501Above & Beyond Construction
13346 Eastbrook Drive Southwest, Port Orchard, WA 98367ADUs offer self-contained living with kitchen, bath & bedroom for rental or family use. Room additions expand existing home space. Above & Beyond Construction serves Seattle & Puget Sound homeowners with both project types.
read moreOther cities in Washington
- Bainbridge Island
- Battle Ground
- Bellevue
- Bellingham
- Bremerton
- Burbank
- Camas
- Edmonds
- Everett
- Fall City
- Federal Way
- Kennewick
- Kent
- Kirkland
- La Center
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.