Skagit Design Homes offers flexible ADU plans for detached units, backyard cottages & granny flats. Maximum ADU sizes vary by local zoning laws. Check municipal regulations early to ensure your accessory dwelling unit project stays on track.read more
Cascade Master Builders builds ADUs in Wenatchee & East Wenatchee, WA. Services include detached, attached, and garage/basement units. They handle permits, pre-approved plans, and financing guidance via HELOC for North Central Washington homeo... read more
Hammer & Hand is a Portland & Seattle general contractor with 30+ years of experience in new homes, remodels, ADUs & commercial builds. Employee-owned, they offer expert craftsmanship, custom woodwork & trusted subcontractor networ... read more
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.read more
Drew Thatcher Construction builds ADUs in Lakewood, WA, including detached units, attached ADUs, and garage conversions. Founded by a Navy nuclear engineer, they offer design-build services with local Pierce County expertise.
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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.
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Raincap Construction, a Seattle-based family-owned contractor, specializes in ADU and DADU construction. They build backyard cottages, in-law suites, and garage conversions, helping homeowners add living space, rental income, and property value.read more
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.
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Brutsky Builds is a licensed ADU contractor in Bellevue offering full-service accessory dwelling unit construction. Services start from $210,000, covering design, permitting, and build completion in ~6 months.
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Precision Tile & Home Remodeling LLC in Kennewick, WA offers ADU, guest house, and in-law suite construction, plus tile work and home remodeling. Quality materials, clear communication, and on-budget delivery are their focus.
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Tacoma DADU Builders is a premier detached ADU builder serving Tacoma and Puget Sound. With 40+ years of experience, they offer turnkey ADU construction—design, permitting, and build—for investors, homeowners, and first-time buyers.
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Microhouse is a Seattle-based ADU builder specializing in custom detached ADUs (DADUs). They guide homeowners through zoning, design, and construction. Seattle permitted 551 DADUs in 2022, with a 40% increase in 2023. Microhouse offers site assess... read more
We specialize in building high-quality, custom Accessory Dwelling Units (ADUs) that provide both functionality and style for homeowners in Port Orchard, WA, and the surrounding areas. Whether you’re looking to add a rental property, create a coz... read more
True Built Home builds custom ADUs in Washington & Oregon, offering 14 floor plans from 495–1,199 sq ft, priced from $119,900. Plans include granny flats, in-law suites & backyard cottages with transparent pricing and customizable design... read more
Gravity Builders LLC is a licensed ADU contractor and custom home builder in Renton, WA. Specializing in ADU/DADU construction, custom homes, outdoor living spaces, and concrete work, they deliver quality craftsmanship with transparency and integr... read more
Washington State has become one of the most ADU-friendly states in the nation, largely due to landmark legislation passed in recent years. In 2023, Washington enacted House Bill 1337, which significantly expanded ADU rights across the state. This law requires cities and counties to allow at least two ADUs per single-family lot, prohibits owner-occupancy requirements, and eliminates many restrictive parking mandates. For homeowners and ADU contractors in Washington, this legislation opened up tremendous opportunities to add accessory dwelling units to residential properties throughout the state.
While HB 1337 sets a statewide baseline, experienced ADU contractors in Washington State must still navigate local building codes and permitting processes that vary by jurisdiction. Cities like Seattle, Bellevue, Tacoma, and Spokane each maintain their own specific requirements regarding setbacks, height limits, and design standards. For example, Seattle allows ADUs up to 1,000 square feet for detached units and has its own streamlined permitting process. A knowledgeable Washington ADU contractor will be well-versed in these local nuances to ensure your project moves forward without costly delays.
Professional ADU builders in Washington are experienced in constructing a wide variety of accessory dwelling unit types to suit different property layouts and homeowner needs. Common ADU types include:
Choosing the right ADU contractor in Washington is critical to the success of your project. Washington State requires all general contractors to be licensed through the Washington State Department of Labor & Industries (L&I). Always verify your contractor holds a valid L&I license and carries proper liability insurance and workers' compensation coverage. Look for contractors with demonstrated experience in ADU construction specifically, as these projects involve unique challenges including utility connections, zoning compliance, and energy code requirements under the Washington State Energy Code (WSEC).
Investing in an ADU with a qualified Washington contractor offers significant long-term advantages. Homeowners can generate rental income to offset mortgage costs, provide housing for aging family members, or increase overall property value. With Washington's high housing demand, particularly in the Puget Sound region, ADUs represent a smart and increasingly accessible investment. Working with an experienced, licensed ADU contractor in Washington State ensures your project is completed safely, legally, and to the highest standards.