Adu housing — Federal Way, WA
Last updated: September 24, 2026
What affects the price
Building an ADU involves several moving parts that shape your total investment. The final figure depends heavily on whether you choose a prefab unit or a custom build from the ground up. Site conditions are another major factor; if your property requires extensive grading, utility trenching, or foundation work, costs will climb. You also have to consider your choice of finishes, like high-end appliances or custom cabinetry. Navigating local permit fees and impact assessments also adds to the total.
About this service
ADU housing refers to the creation of independent living quarters on a property that already has a primary house. This is a common solution for multi-generational families or those looking for rental income. Whether you are building a studio or a two-bedroom unit, it provides a private kitchen, bathroom, and living area. You need this if you want to maximize your property's utility without moving. Exact pricing confirmed free on the call.
Frequently asked in Federal Way
Where can I find an accessory dwelling unit near me?
What permits are required for an ADU?
Permits for an ADU in Federal Way are essential and typically include building permits, zoning permits, and potentially others depending on the project's scope. These ensure your ADU complies with all local codes and regulations. Your contractor will guide you through obtaining all necessary permits. This is a critical step for legal construction. We help you find the right guidance.
Are there accessory dwelling units in New Hampshire?
What is a modular accessory dwelling unit?
A modular accessory dwelling unit is constructed in sections off-site in a factory and then transported to your Federal Way property for assembly. This method often offers faster construction times and consistent quality control. These units are designed to be fully functional, independent living spaces. They provide an efficient and reliable building solution. It's a modern approach to creating ADUs.
Do you offer ADU estimates?
Where can I find accessory dwelling unit builders near me?
What are homes with in-law suites?
Homes with in-law suites feature a separate, self-contained living space within or attached to the main residence. This suite typically includes a bedroom, bathroom, and often a kitchenette. It's designed for independent living for family members or as a rental unit. It's a popular feature for added flexibility. It enhances your home's utility.
Also serving nearby: Tacoma · Kent · Renton · Seattle · Bellevue
More on this: HUD ADU resources — ADU policy and financing research.
Service area details
Serving all of Federal Way — population 97,701; about 4,375 residents per square mile across 22.3 sq mi. ZIP codes covered include 98003, 98023, 98063, 98093.
Neighborhoods served in Federal Way: Kenter Heights, The Lakes, Redondo Heights, Weyerhaeuser, Twin Lakes — and every surrounding area.
Areas we serve
Browse by state, then city.