ADU Contractors near Federal Way, WA
Tenhulzen Construction
16900 9th Avenue Southeast, Mill Creek, WA 98012
37.4 miles
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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Ballard Backyard Cottages
4142 2nd Avenue Northwest, Seattle, WA 98107
24.1 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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Coates Design Architects
900 Winslow Way East, Bainbridge Island, WA 98110
23.3 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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Above & Beyond Construction
13346 Eastbrook Drive Southwest, Port Orchard, WA 98367
21.1 miles
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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Pelletier Construction Group
1150 North 84th Street, Seattle, WA 98103
26.3 miles
Chapman Projects
4225 335th Place Southeast, Fall City, WA 98024
27.3 miles
Chapman Projects offers ADU design and construction in Seattle, Bellevue, and King County. With 20+ years of experience, they provide custom accessory dwelling units, detached ADUs, and backyard cottages using sustainable building practices.
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Cascadia ADU
901 1st Street, Snohomish, WA 98290
43.5 miles
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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North West Builders & Renovations
1135 Lake Washington Boulevard North, Renton, WA 98057
14.8 miles
Greater Seattle Remodeling
1850 130th Ave NE #1, Bellevue, WA 98005
22.9 miles
Greater Seattle Remodeling builds code-compliant ADUs across the Seattle metro, including detached ADUs, garage conversions, and basement apartments. They match homeowners with vetted contractors for permits, design, and construction.
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Better Builders
5606 California Avenue Southwest, Seattle, WA 98136
16.9 miles
Better Builders is a Seattle-based general contractor specializing in residential remodeling, garage conversions, ADUs, kitchen and bathroom remodels, basement finishing, deck repairs, and exterior work, with dedicated project management.
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Red's Construction & Renovation
Federal Way, WA 98003
1.2 miles
Red's Construction & Renovation serves Federal Way & South King County, WA, specializing in ADU construction including detached, attached, garage conversions & basement units. Costs range from $50K–$300K+. Licensed, insured, transparent pricing.
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Deane Home Services
17837 1st Avenue South, Normandy Park, WA 98148
9.2 miles
Deane Home Services builds ADUs in South King County, WA, including garage conversions, basement remodels, and detached backyard cottages. Licensed, bonded & insured. Serving Kent, Renton, Federal Way & more.
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True Built Home
3403 North Proctor Street, Tacoma, WA 98407
7.5 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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Cast Architecture
115 North 36th Street, Seattle, WA 98103
23.8 miles
Cast Architecture specializes in ADU and backyard cottage design in Seattle since 2009. With 80+ projects, their Cedar Cottage is pre-approved by Seattle & Kirkland. Award-winning designs include Widner Cottage and Lichtenstein Studio. Visit castcottages.com.
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Exceptional Home Builders Seattle
1525 11th Avenue, Seattle, WA 98122
21.1 miles
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.
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Other cities in Washington
What you need to know
ADU Contractors in Federal Way, WA: Building in a Growing South King County City
Federal Way, Washington, is one of the fastest-growing cities in South King County, with a diverse population and a strong demand for affordable housing solutions. As the city continues to expand, Accessory Dwelling Units (ADUs) have become an increasingly popular option for homeowners looking to add rental income, house extended family members, or increase property value. Working with experienced ADU contractors in Federal Way, WA is essential to navigating the city's specific zoning codes, permitting requirements, and construction standards.
Federal Way ADU Regulations and Zoning Requirements
Federal Way operates under its own municipal code, separate from King County, which means ADU regulations are governed by the Federal Way Revised Code (FWRC). Homeowners and contractors must be familiar with these local rules before beginning any ADU project. Key regulations include:
- ADUs are permitted in single-family residential zones, including RS 5.0, RS 7.2, RS 9.6, and RS 35.0 zones.
- Both attached ADUs and detached ADUs (DADUs) are allowed, subject to lot size and setback requirements.
- The maximum size for a detached ADU is typically 1,200 square feet or 50% of the primary dwelling's square footage, whichever is less.
- Owner-occupancy requirements may apply, meaning the property owner must reside in either the primary home or the ADU.
- Setbacks, lot coverage limits, and height restrictions must all be carefully reviewed before design begins.
The Permitting Process for ADUs in Federal Way
Obtaining the proper permits is a critical step in any ADU construction project in Federal Way. The Federal Way Community Development Department oversees building permits, and all ADU projects must comply with Washington State Building Code (WSBC) as well as local amendments. A qualified ADU contractor in Federal Way will handle the full permitting process, including submitting architectural plans, site plans, and engineering documents. Permit timelines can vary, so working with a contractor experienced in Federal Way's specific review process can help avoid costly delays.
What to Look for in Federal Way ADU Contractors
Choosing the right contractor for your ADU project in Federal Way is crucial to a successful outcome. Here are some important qualities to look for:
- Local experience: Contractors familiar with Federal Way's zoning codes and permitting process will save you time and money.
- Licensing and insurance: Always verify that your contractor holds a valid Washington State contractor's license and carries liability insurance.
- Design-build capabilities: Contractors who offer both design and construction services can streamline the entire ADU process.
- Transparent pricing: Look for detailed, itemized estimates to avoid unexpected costs during construction.
Invest in an ADU in Federal Way Today
With Federal Way's growing rental market and rising property values, building an ADU is a smart long-term investment. Whether you're considering a garage conversion, basement ADU, or a brand-new detached unit, partnering with a knowledgeable ADU contractor in Federal Way, Washington ensures your project meets all local requirements and is completed to the highest standard. Start your ADU journey today and take advantage of one of South King County's most promising housing opportunities.