Basement Conversion in Washington

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.

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.

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.

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.

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.

Tiny Cottage Builders NW offers ADU construction, garage conversions, basement finishing & home remodeling in Tri-Cities, WA. Led by Brandon Lott, every project is personally managed ensuring quality craftsmanship & clear communication.

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.

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.

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.

Huskies Construction in Renton specializes in home additions, ADUs, and DADUs. Services include garage conversions, granny flats, in-law suites, backyard cottages, and room additions, helping homeowners expand living space or generate rental income.

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 Bellevue, WA.

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 & permit-ready plans included.

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 lot.

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.

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.