ADUs & conversions · Federal Way, WA
Attached ADU Build in Federal Way, WA
Attached accessory dwelling units within the home's footprint.
Attached ADU Build in Federal Way, WA
Xion Build provides expert attached ADU build in Federal Way. As a trusted Federal Way adus & conversions contractor, we manage design, materials, permits, and every trade in-house so your project stays on schedule and on budget. Attached accessory dwelling units within the home's footprint.
Federal Way's established neighborhoods reward durable, value-driven remodels, roofing, and exterior work.
We write scope in plain terms: what we'll do, the materials, the sequence, and how any surprises are handled if something is uncovered.
What's included in your attached ADU build
A typical attached ADU build in Federal Way can involve the kitchen and bath, finishes, utilities, permits — and we put the full scope in writing so you know exactly what's covered before work starts.
You get a single point of contact, licensed and insured trades, and clear communication from the first sketch to the final walkthrough.
How much does an attached ADU build cost in Federal Way?
Most attached ADU build projects in Federal Way fall between $151,500 – $454,500, depending on the size of the space, the finishes you choose, and the condition of what's already there.
Because every home is different, we don't quote final numbers sight unseen. After a free in-home consultation you get a detailed, itemized estimate tied to your actual adus & conversions project — so there are no surprises later.
Why Federal Way homeowners choose Xion Build
One dedicated point of contact coordinates the entire job, so you're never chasing subcontractors or wondering who's responsible.
Honest guidance on where to invest and where to save, so your budget goes toward what adds real, lasting value.
Licensed, bonded, and insured in Washington — every project is built to meet or exceed code and backed by a written warranty.
Our Federal Way adus & conversions process
Handoff includes a detailed walkthrough and a written warranty — not a crew that vanishes the moment the dust settles.
Design and material selections come next, so finishes, fixtures, and pricing are locked in before demolition — no surprises mid-project.
Each phase is inspected and documented, and we keep you updated so you always know what's happening and what's next.
Frequently asked questions
Do you offer free estimates for attached ADU build near Federal Way?
Absolutely. We provide free, no-obligation in-home estimates throughout Federal Way and the greater Eastside, with transparent, itemized pricing.
Are you a licensed adus & conversions contractor?
Yes — Xion Build is licensed, bonded, and insured in WA. Every project is built to meet or exceed code and is backed by a written warranty.
How much does an attached ADU build cost in Federal Way?
Most attached ADU build projects in Federal Way run $151,500 – $454,500, depending on scope, finishes, and existing conditions. After a free in-home consultation we provide a detailed written estimate so your Federal Way price reflects the actual project — not a guess.
What should we decide before starting an attached ADU build?
Your budget range, must-haves, timeline, and any finishes you already love. For adus & conversions work we also review access, existing conditions, and whether permits are required in Federal Way.
Do you handle permits and inspections?
Yes. We manage permit applications, schedule inspections, and coordinate any required engineering so the work passes cleanly in Federal Way.
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