Basement Conversion in Washington
The DADU Guy
2522 North Proctor Street, Tacoma, WA 98406
The DADU Guy is a Tacoma-based detached ADU builder serving Pierce County, WA. Specializing in DADUs, garage conversions, and basement conversions, they offer 5 floor plans, guaranteed pricing, and full project management to maximize property value.
read more
Rybak & Company LLC
19215 Southeast 34th Street, Camas, WA 98607
Rybak & Company LLC builds ADUs in Vancouver, Camas, Washougal & Portland Metro. Services include detached ADUs, garage conversions & in-law suites. Projects start at $175K–$250K+. Free estimates available.
read more
Cascade Master Builders
209 River Park Ave, Unit 1, Wenatchee, WA 98801
Cascade Master Builders builds ADUs in Wenatchee & East Wenatchee, WA. Services include detached, attached, and garage/basement units. They handle permits, pre-approved plans, and financing guidance via HELOC for North Central Washington homeowners.
read more
Bellingham ADU Builders
2111 King Street, Bellingham, WA 98225
Bellingham ADU Builders offers full-service ADU construction in Whatcom County, including detached and attached ADUs. Costs range from $200K–$550K+. Permits included. Free 48-hour feasibility study available. HB 1337 allows up to two ADUs per lot.
read more
Better Builders
5606 California Avenue Southwest, Seattle, WA 98136
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.
read more
Marksymov Brownstone
12814 Northeast 139th Street, Kirkland, WA 98034
Marksymov Brownstone LLC is a licensed Seattle ADU contractor offering basement, garage & attic conversions. They handle design, permits & construction, ensuring code compliance across Seattle, Bellevue & Kirkland.
read more
Heartwood Builders
1902 North 34th Street, Seattle, WA 98103
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.
read more
Other cities in Washington
What you need to know
Searching for top Basement Conversion ADU Contractors in Washington? Our directory highlights trusted local professionals who specialize in designing and building accessory dwelling units (ADUs).
Working with a qualified Basement Conversion ADU Contractor in Washington ensures your ADU project meets local building codes, zoning laws, and permit requirements. Whether you're planning a detached ADU, garage conversion, or backyard cottage, experienced Basement Conversion professionals can guide you through every step.
Washington homeowners are increasingly investing in ADUs to create additional living space, generate rental income, or support multigenerational living. The Basement Conversion experts featured here bring local expertise and proven experience to help make your project a success.
Browse our listings to find the best Basement Conversion ADU Contractors in Washington, and get started today.