Detached ADU in Washington

Lindal 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.

FTS Excavation offers full-service ADU site development in South Puget Sound, Western Washington. Services include grading, utilities, septic systems, foundation excavation & permits. Certified, reliable ADU contractor for backyard homes & accessory dwelling units.

Seattle's 2019 ADU law changes made it easier to build accessory dwelling units on single-family lots. DADUs can't exceed 50% of the main home's size. No parking required. New detached ADUs start around $350,000.

ADA Boomer references the Americans with Disabilities Act and the aging ‘Boomer’ generation. Our focus on accessibility has stemmed from observing that most homes do not work well for people with mobility issues.

Alfa Framing offers residential construction services including structural framing, siding installation, roofing, and ADU/DADU construction. Serving new builds and additions, they bring decades of experience and a solution-oriented approach.

Exceptional 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.

For more than 15 years, we’ve turned backyards into beautifully crafted living spaces. From permits to finishing touches, our team knows every step inside and out. Choose the classic charm of our Traditional Series, the clean lines of our Modern Series or the efficiency and flexibility of our Urban Series. Build with the crew that wrote the ADU playbook: RG ProBuilders.

Greater 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.

VDC Builders Inc specializes in ADU design & construction, including backyard cottages, in-law suites & rental units. Services cover flooring, kitchen & bathroom remodels, custom home building & cabinet refinishing.

Red's Construction & Renovation serves Federal Way & South King County, WA, specializing in ADU construction including detached, attached, garage conversions & basement units. Costs range from $50K–$300K+. Licensed, insured, transparent pricing.

Giant Builders Seattle is a Kent, WA general contractor with 20+ years of experience offering ADU construction, garage conversions, kitchen & bathroom remodeling, room additions, roofing, deck building, and more.

Emerald ADU Builders Seattle specializes in ADU design, permitting, and construction. They build detached ADUs, attached ADUs, and garage conversions, serving Seattle homeowners with quality craftsmanship and transparent pricing.

Evola Builds LLC, led by Michael and Amber Evola, offers residential renovation and construction services including bathroom remodels, ADU work, garage conversions, and structural modifications, collaborating closely with architects and homeowners.

Rybak & Company LLC builds ADUs in Vancouver, Camas, Washougal & Portland Metro. Services include detached ADUs, garage conversions & in-law suites. Projects start at $175K–$250K+. Free estimates available.

Northwest ADU is a full-service ADU contractor in Western Washington specializing in detached ADUs, garage conversions, and basement conversions. Serving Pierce, King, and Snohomish Counties, projects range from $180K–$350K+, taking 6–10 months.