ADUs offer self-contained living with kitchen, bath & bedroom for rental or family use. Room additions expand existing home space. Above & Beyond Construction serves Seattle & Puget Sound homeowners with both project types.
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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.... read more
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.
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Twin Brothers Group is a licensed framing contractor in Washington State specializing in ADU, DADU, garage conversions, and home additions across King and Snohomish County, serving Seattle-area GCs and owner-builders.
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FTS Excavation offers full-service ADU site development in South Puget Sound, Western Washington. Services include grading, utilities, septic systems, foundation excavation & permits. Certified, reliable ADU contractor for backyard homes &... read more
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 fa... read more
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.
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Elite Team Builders Inc. designs & builds ADUs—detached units, garage conversions & backyard cottages—in Seattle, Portland & Los Angeles. They offer custom design, quality materials & transparent pricing for lasting residential... read more
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.
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HiLine Homes is an experienced ADU builder in Idaho with nearly 30 years in custom home construction. They offer attached and detached ADU designs for rental income, multigenerational living, or home offices, with financing options available.
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Tenhulzen Construction offers ADU and DADU construction services in Washington State, providing pre-approved and custom plans. Options suit various budgets and timelines, with benefits including added property value and flexible living spaces.
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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
Sockeye Homes designs & builds custom ADUs and DADUs, offering full-service support from permits to construction. Fixed-cost packages range from $218K–$335K+, suiting retirees, families & rental income seekers.
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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 th... read more
Mercer Island, Washington, is a distinctive residential community situated entirely on an island in Lake Washington, connected to Seattle and Bellevue via Interstate 90. This unique geography creates specific challenges and opportunities for ADU contractors in Mercer Island. The city is known for its affluent, tree-lined neighborhoods, strict environmental protections, and limited land availability — all factors that make accessory dwelling units (ADUs) an increasingly attractive solution for homeowners looking to maximize their property's potential.
Before breaking ground, experienced Mercer Island ADU contractors must be well-versed in the city's specific zoning codes and building regulations. Mercer Island falls under King County jurisdiction for some matters but maintains its own municipal code. Key regulations homeowners and contractors need to understand include:
Given the island's predominantly single-family residential character and lot configurations, ADU builders in Mercer Island, WA most frequently work on the following project types:
Working with a licensed ADU contractor familiar with Mercer Island is essential for a smooth permitting and construction process. Local contractors understand the nuances of building on island terrain, including managing utility connections, dealing with the city's permit office, and respecting the community's high aesthetic standards. Mercer Island homeowners consistently prioritize quality craftsmanship and design that complements the area's natural beauty and upscale character.
Whether you're looking to create a rental income unit, house family members, or increase your property value, an ADU is a smart investment in Mercer Island's competitive real estate market. Connect with a qualified ADU contractor serving Mercer Island, Washington to discuss your project goals, review local code requirements, and begin the design and permitting process with confidence.