Basement Conversion near Federal Way, WA

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.

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.

Top Volk Construction builds ADUs in the Seattle area, including detached backyard cottages, attached units, garage conversions, and basement ADUs. This licensed contractor manages design, permitting, construction, and inspections for homeowners s... read more

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.

Home Care Contractors builds ADUs in King County, including DADUs, garage conversions, and basement units. They handle permits, design, and construction. Costs range from $300K–$700K, with timelines of 7–13 months total.

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 incom... read more

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.

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 month... read more

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, transpar... read more

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.

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

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.

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

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 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