Armada Design & Build Inc., Bellevue, WA, offers full-service residential design-build since 2011. Specializing in remodels, home additions, and custom builds across Puget Sound, they deliver turnkey solutions with in-house design and quality ... 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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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 sp... read more
SkyDADU is a DADU builder and equity partner serving King, Snohomish, and Pierce counties in Washington State. They offer fixed-price packages, up to 100% funding, and handle permitting, construction, and condominiumization for detached accessory ... read more
BB Builders Pro specializes in ADU construction, garage conversions, home additions, and detached backyard cottages. Services include custom design, permitting, zoning compliance, and renovations—ideal for rental income or family housing.
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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.
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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,... read more
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.
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NW Build specializes in ADU & DADU construction in Bellevue and the Puget Sound region. They manage permits, design, and builds for detached ADUs, attached units, and granny flats, adding value to residential properties.
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Era Builders is a Seattle-based ADU contractor offering detached ADU construction, design, permitting, remodeling, and commercial renovations. They handle full ADU projects compliant with Seattle zoning rules, using sustainable practices.
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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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Seattle Backyard Homes builds expert ADUs, DADUs, garage conversions & backyard cottages in Seattle and Bellevue. Full-service ADU contractors handling design, permits, zoning & construction with quality craftsmanship and transparent prici... read more
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.
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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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Alfa Framing offers residential construction services including structural framing, siding installation, roofing, and ADU/DADU construction. Serving new builds and additions, they bring decades of experience and a solution-oriented approach.
read moreMercer 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.