Attached ADU near Marysville, WA

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.

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.

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 ADU is a Seattle-based contractor specializing in accessory dwelling units, including detached ADUs, garage conversions, attached ADUs, and JADUs. They manage design, permitting, and construction for homeowners seeking additional living space.

Lakeside ADU & Home Planning, based in Lake Stevens, WA, is a full-service ADU builder serving the Puget Sound Region. They specialize in backyard cottages, mother-in-law suites, garage conversions, and new builds, managing design, permitting, and construction.

Seattle's trusted DADU & ADU builder offers custom builds, ADU conversions, and prefab cabins. Transparent pricing, expert guidance, and hands-on construction help homeowners add lasting value with backyard cottages and granny flats.

Backyard ADU is a full-service ADU contractor managing every stage of accessory dwelling unit builds, including feasibility, permits, site surveys, foundations, construction, utility connections, and condo legal services.

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.

Neil Kelly Washington offers ADU design and build services in the Northwest, including detached ADUs, garage conversions, and attached units. Their team navigates local permits, balances design with functionality, and helps homeowners add value through custom accessory dwelling units.

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.

Lindal Homes offers custom ADU and DADU kit home solutions across the US and Canada. Flexible floor plans, the Lindal Elements collection, and system-built construction make adding a backyard cottage or guest suite efficient and cost-effective.

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 ensure smooth project execution.

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.