Detached ADU near Mill Creek, WA

Raincap Construction, a Seattle-based family-owned contractor, specializes in ADU and DADU construction. They build backyard cottages, in-law suites, and garage conversions, helping homeowners add living space, rental income, and property value.read more

J Hanby LLC offers ADU and basement conversion services in the Eastside area. Specializing in detached ADUs, garage conversions, granny flats, and basement renovations, they help homeowners maximize property value and ROI.

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.

An ADU (accessory dwelling unit) is a secondary dwelling on a single-family lot. Types include basement apartments, garage conversions & detached cottages. Costs vary by size, design, permits & materials. Professional ADU contractors ensur... read more

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.

Twin Brothers Group is a licensed framing contractor in Washington State specializing in ADU, DADU, garage conversions, and home additions across King and Snohomish County, serving Seattle-area GCs and owner-builders.

Zee Design & Build is a Kirkland, WA ADU contractor serving King, Snohomish, Skagit & Island Counties. Offering full-service ADU construction—garage conversions, basement units, backyard cottages & more—since 2012.

Harjo Construction builds AADUs & DADUs in Seattle with 300+ projects since 2010. Costs range $275K–$650K, max 1,000 sq ft, 4–6 month build time. Seattle removed owner-occupancy rules, boosting ADU rental potential.

Seattle 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

Gordon T. Jacob is a family-run ADU builder and home remodeling contractor in South Puget Sound. Specializing in detached ADUs, backyard cottages, middle housing, and full home renovations in the Tacoma area.

Cascadia 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.

Puget Sound ADU Builders is a leader in ADU construction in western Washington state, excelling in design, construction, finishing, and permitting ADUs, DADUs, backyard cabins, garage conversions, duplexes, town homes, and multi-unit projects.

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.

An Accessory Dwelling Unit (ADU) is an independent living space on a single-family property. Washington State's HB 1337 boosted ADU construction, easing zoning rules, removing owner-occupancy requirements, and capping impact fees at 50%.

NW Finishing is a Seattle-area ADU contractor offering full-service accessory dwelling unit design and construction. Serving Bellevue, Kirkland, Redmond, Renton, and more, they handle permits, planning, and builds for detached, cottage, and prefab... read more