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ADU Contractors near Federal Way, WA
Doyle Construction
300 Deschutes Way Southwest, Tumwater, WA 98501 33.3 milesSeattle Modern Buildings ADU Builder
8305 Dallas Avenue South, Seattle, WA 98108 15.2 milesSeattle Modern Buildings ADU Builder is a Seattle-based design-build firm specializing in detached ADUs, duplexes, and modern homes. With deep knowledge of Seattle permitting, zoning, and construction best practices, we help homeowners unlock thei... read more
Sockeye Homes
14638 SE 229th Pl, Kent, WA 98042 10.7 milesSockeye 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.
read moreTrue Built Home
3403 North Proctor Street, Tacoma, WA 98407 7.5 milesTrue 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
Cascadia ADU
901 1st Street, Snohomish, WA 98290 43.5 milesCascadia 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.
read moreSeattle ADU
509 Olive Way, Seattle, WA 98101 21 milesSeattle 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
Hammer & Hand
2450 6th Avenue South, Seattle, WA 98134 18.7 milesHammer & 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
NorthLight Custom Builders
9800 Harbour Place, Mukilteo, WA 98275 41.3 milesNorthLight Custom Builders offers ADU construction in King & Snohomish County. Services include attached & detached units for rental income, family living, or home offices. Structured process from consultation to one-year warranty follow-u... read more
Ballard Backyard Cottages
4142 2nd Avenue Northwest, Seattle, WA 98107 24.1 milesSeattle'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.
read moreHiLine Homes
11306 62nd Avenue East, Puyallup, WA 98373 7.8 milesHiLine 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.
read moreAvio Homes
10908 62nd Street East, Puyallup, WA 98372 7.8 milesAvio Homes is a Seattle-based ADU contractor specializing in detached ADUs, backyard cottages, and in-law suites. Serving Seattle, Tacoma, and Olympia, they handle design, permitting, and construction with local zoning expertise.
read moreInterbay Construction
1020 108th Avenue Northeast, Bellevue, WA 98004 22.4 milesInterbay Construction is a Washington State ADU contractor building guest houses, in-law suites, detached ADUs & backyard cottages. Quality materials, clear communication & reliable timelines for every accessory dwelling unit project.
read moreJayMarc Homes
7525 Southeast 24th Street, Mercer Island, WA 98040 19.8 milesAn Accessory Dwelling Unit (ADU) is an independent living space on a single-family property. Washington State's HB 1337 boosted ADU construction, easing zoning rules, removing owner-occupancy requirements, and capping impact fees at 50%.
read moreGravity Builders LLC
17422 108th Avenue Southeast, Renton, WA 98055 11.5 milesGravity 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
Other cities in Washington
- Bainbridge Island
- Battle Ground
- Bellevue
- Bellingham
- Black Diamond
- Bothell
- Bremerton
- Burbank
- Camas
- Edmonds
- Everett
- Fall City
- Kennewick
- Kent
- Kirkland
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.