Basement Conversion near Port Townsend, WA

RT Signature Homes, a Redmond, WA-based ADU contractor and design-build firm, builds detached and attached ADUs, garage conversions, and in-law suites, managing feasibility review, permitting, and construction for functional residential living spa... read more

Northwest ADU is a trusted ADU builder in Mill Creek, WA, offering full-service accessory dwelling unit construction, including detached ADUs, garage conversions, and basement conversions, with expert permit and zoning support.

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

Levite Construction Co is a Seattle-based family-owned general contractor offering kitchen remodeling, bathroom remodeling, ADU construction, garage conversions, new builds, interior design, and more across the Greater Seattle area.

Bellingham 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

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.

LYD Construction is a Seattle-area ADU builder & remodeling contractor with 25 years of experience. Services include kitchen, bathroom, basement renovations, deck building & ADU construction. Financing up to $200,000 available. Based in Be... read more

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

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.... read more

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.

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.

New 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.

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

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.

Explore pre-designed ADU floor plans from Modern ADU Plans — studio, 1-bed, 2-bed, garage conversions & more. Save time, reduce costs & maximize property value with ready-to-build accessory dwelling unit designs.