Detached ADU in Washington

Bicknell Builds offers ADU construction in the greater Seattle area, including detached ADUs, backyard cottages, granny flats, and in-law suites. Ideal for rental income, family housing, or added property value.

ModernSpace ADU Construction is a certified ADU builder serving Redmond, offering tailored accessory dwelling unit services. Competitive pricing, no hidden fees, and a satisfaction guarantee make them a trusted local choice.

Cruvers Contracting LLC builds ADUs in Snohomish, WA, tackling rural challenges like septic systems, slopes, and wooded lots. Serving areas including Lake Stevens, Monroe, and Everett with phased planning and durable, site-specific construction.

New Image Construction Management is a Washington State general contractor and building company based in Seattle, WA. With a primary focus of new home construction and renovation of residential and commercial properties.

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.

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.

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.

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.

Carriage Houses NW is a Pacific Northwest ADU builder specializing in infill housing. They develop ADUs, duplexes, and townhomes, partner with homeowners, and offer fee-to-build services, leveraging WA State HB 1110 and HB 1337 legislation.

At Puget Sound ADU Builders, we create functional and cozy and ADUs (Accessory Dwelling Units) in Washington. Our company was founded by Tanya Mills and built on a passion for providing high-quality, affordable housing solutions that unite families. With rising costs in traditional housing and care, we offer practical alternatives that allow your loved ones to live independently in comfortable spaces—right in your backyard.

Haas Development & Construction offers ADU & DADU construction in Greater Seattle. They handle planning, permits, design, and builds for attached & detached units, including prefab DADU plans, helping homeowners add rental income or family housing.

Fortitude Construction Group is a Spokane-based design-build contractor specializing in custom ADUs, home additions, and new builds. Led by experienced professionals, they serve Spokane and surrounding areas with integrity-driven craftsmanship.

Alta Casa Remodeling is a Vancouver, WA ADU builder specializing in accessory dwelling units, garage conversions, in-law suites, and home additions. They also offer kitchen, bathroom, and full home remodels, backed by a one-year workmanship warranty.