ADU Contractors near Seattle, WA
True Built Home
3403 North Proctor Street, Tacoma, WA 98407
24.9 miles
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 designs.
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Coates Design Architects
900 Winslow Way East, Bainbridge Island, WA 98110
8.7 miles
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.
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Bicknell Builds
19616 Southeast 310th Place, Kent, WA 98042
23.3 miles
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.
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NW Build
2265 116th Avenue Northeast, Bellevue, WA 98004
6.4 miles
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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Heartwood Builders
1902 North 34th Street, Seattle, WA 98103
1.9 miles
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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Era Builders
911 Northeast 70th Street, Seattle, WA 98115
4 miles
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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Backyard ADU
4813 37th Avenue Northeast, Seattle, WA 98105
3.6 miles
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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Gordon T. Jacob - Multifamily | DADU | Remodel
6901 81st Street Court East, Puyallup, WA 98371
31 miles
Gordon T. Jacob is a family-run ADU builder and home remodeling contractor in South Puget Sound. Specializing in detached ADUs, backyard cottages, middle housing, and full home renovations in the Tacoma area.
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Harmony Architecture Studio
1324 Lombard Avenue, Everett, WA 98201
25.6 miles
Seattle Backyard Homes
4813 37th Avenue Northeast, Seattle, WA 98105
3.6 miles
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 pricing.
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Cruvers Contracting LLC
1002 Pine Avenue, Snohomish, WA 98290
22.7 miles
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.
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Seattle Remodeling LLC
17202 Aurora Avenue North, Shoreline, WA 98133
9.2 miles
Seattle Remodeling LLC specializes in ADU construction in Seattle, offering mother-in-law suites, backyard cottages, garage conversions, and granny flats. They help homeowners add value, rental income, and flexible living space.
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Zee Design & Build
570 Kirkland Way, Kirkland, WA 98033
7.1 miles
Zee Design & Build is a Kirkland, WA ADU contractor serving King, Snohomish, Skagit & Island Counties. Offering full-service ADU construction—garage conversions, basement units, backyard cottages & more—since 2012.
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New Day Construction
15021 116th Place Northeast, Kirkland, WA 98034
10.3 miles
New Day Construction is a licensed ADU builder in Bellevue, WA, with 21+ years of experience and 250+ projects. They build detached, attached, garage, basement, and custom ADUs, managing permits and design from start to finish.
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Ballard Backyard Cottages
4142 2nd Avenue Northwest, Seattle, WA 98107
3 miles
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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Other cities in Washington
What you need to know
Seattle's Progressive ADU Policies Make It a Leader in Accessory Dwelling Units
Seattle, Washington has become one of the most ADU-friendly cities in the United States. In 2019, the city passed landmark legislation that significantly relaxed restrictions on Accessory Dwelling Units (ADUs), allowing homeowners to build both an attached ADU and a detached ADU (DADU) on the same property simultaneously. This progressive policy shift has created a booming demand for experienced ADU contractors in Seattle, making it essential to find professionals who understand the city's unique regulatory landscape.
Key Seattle ADU Regulations Your Contractor Must Know
Hiring a knowledgeable Seattle ADU contractor means working with someone who is well-versed in the city's specific building codes and zoning requirements. Seattle's Department of Construction and Inspections (SDCI) oversees all ADU permits, and navigating this process requires expertise. Some critical regulations include:
- No owner-occupancy requirement, meaning landlords can rent out both the primary home and the ADU
- Detached ADUs can be up to 1,000 square feet in size
- ADUs can be up to 24 feet tall in most zones
- No off-street parking is required for ADUs located near frequent transit service
- Up to two ADUs are permitted per lot in single-family and low-rise zones
What to Look for in a Seattle ADU Contractor
Finding the right ADU builder in Seattle is critical to the success of your project. The city's hilly terrain, frequent rainfall, and older housing stock present unique construction challenges. A qualified contractor should have experience working with Seattle's soil conditions, understanding of stormwater management requirements, and familiarity with the city's energy code, which aligns with Washington State's strict energy efficiency standards. Always verify that your contractor holds a valid Washington State contractor's license and carries proper liability insurance.
The ADU Permitting Process in Seattle
The permitting process for ADUs in Seattle can be complex and time-consuming. Working with an experienced Seattle ADU contractor who understands the SDCI's online permitting portal and plan review process can save significant time and money. The typical steps include:
- Pre-application research and site assessment
- Design and architectural plan preparation
- Permit application submission through Seattle's ePlans system
- Plan review and corrections
- Permit issuance and construction
- Final inspections and certificate of occupancy
Why Investing in an ADU in Seattle Makes Financial Sense
With Seattle's consistently high rental demand and competitive housing market, building an ADU is a smart financial investment. Seattle ADU contractors report strong interest from homeowners looking to generate rental income, house family members, or increase overall property value. Whether you're considering a backyard cottage, a garage conversion, or a basement ADU, partnering with a skilled and licensed contractor who knows Seattle's building environment is the key to a successful and compliant project.