Basement Conversion in Washington

Our team specializes in ADU construction and home remodeling, creating functional, well-designed spaces with quality craftsmanship and attention to detail.

Heartwood Builders is a Seattle ADU contractor specializing in backyard cottages, basement ADUs, and mother-in-law suites. They handle permitting, use sustainable materials, and help homeowners add rental income or family housing.

Seattle ADU & DADU contractor Emerald City Construction & Renovation builds accessory dwelling units across Seattle, Bellevue & Eastside. Projects cost $350K–$500K+, take 8–14 months, and support rental income, multigenerational li... read more

Love Construction builds ADU & DADU units in Seattle & Puget Sound to Passive House standards. Attached ADUs cost $85K–$280K; DADUs $175K–$550K. Includes permitting, energy modeling & a 5-year warranty.

Better Builders is a Seattle-based general contractor specializing in residential remodeling, garage conversions, ADUs, kitchen and bathroom remodels, basement finishing, deck repairs, and exterior work, with dedicated project management.

Integrity Remodeling Inc is a Spokane, WA contractor specializing in ADU construction, garage conversions, and accessory dwelling units. Services include backyard cottages, basement apartments, in-law suites, and rentable ADUs for added property v... read 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.

Homez Remodel is a Seattle ADU builder specializing in DADUs, backyard cottages, garage conversions & basement ADUs. With 10+ years experience, they handle permits, design & construction across Seattle, Bellevue, Kirkland & more.

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.

Northwest ADU builds custom detached ADUs, garage conversions & basement ADUs across Western Washington. Serving King, Pierce & Snohomish Counties with full-service ADU construction, build-ready plans & permit management.

Deane 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.

Cascade Master Builders builds ADUs in Wenatchee & East Wenatchee, WA. Services include detached, attached, and garage/basement units. They handle permits, pre-approved plans, and financing guidance via HELOC for North Central Washington homeo... 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.

JDI Construction is a Portland-based ADU contractor offering full design-build services for detached, attached, garage conversion, basement, above-garage, and interior ADUs, including permits and eco-friendly practices.