
Rainier Custom Homes
Rainier Custom Homes. Custom home builder. 451 SW 10th St Suite 105, Renton, WA 98057, United States
Looking for the best custom ADU builders in Renton, Washington? Our directory features 2 vetted custom adu builders serving the Renton area. Whether you're planning a new ADU construction, garage conversion, or backyard cottage, find the right builder for your project.

Rainier Custom Homes. Custom home builder. 451 SW 10th St Suite 105, Renton, WA 98057, United States

Pan Abode Cedar Homes Inc. Custom home builder. 1100 Maple Ave SW, Renton, WA 98057, United States
Renton is one of the top markets for accessory dwelling units in Washington. With growing demand for affordable housing, ADU construction in Renton offers homeowners an excellent opportunity to add living space, generate rental income, or house family members. Our curated list of custom adu builders in Renton helps you find experienced professionals who understand local building codes, zoning regulations, and permit requirements.
ADU construction costs in Renton typically range from $150,000 to $350,000 depending on size, design, and finishes. Garage conversions are generally less expensive ($80,000–$150,000), while custom-built detached ADUs can cost more. Get free quotes from our listed custom adu builders to compare prices.
Yes, ADU construction in Renton requires building permits. Washington has specific ADU regulations, and local zoning laws may have additional requirements. Our listed builders can help you navigate the permitting process.
ADU construction timelines in Renton typically range from 4–12 months, depending on the project type. Prefab ADUs can be installed in 2–4 months, while custom builds may take 8–12 months including design and permitting.