ADUs & conversions · Seattle, WA
Detached ADU (DADU) Build in Seattle, WA
Stand-alone backyard cottages from foundation to finish.
Detached ADU (DADU) Build in Seattle, WA
When Seattle homeowners search for detached ADU (DADU) build or a dependable adus & conversions contractor near them, they want craftsmanship that lasts and a crew that communicates. That's exactly what we do. Stand-alone backyard cottages from foundation to finish.
From Laurelhurst to Queen Anne, Seattle's older homes often need structural care alongside the kitchen, bath, and addition work that modernizes them.
You get a single point of contact, licensed and insured trades, and clear communication from the first sketch to the final walkthrough.
What's included in your detached ADU (DADU) build
A typical detached ADU (DADU) build in Seattle can involve framing, foundation, the kitchen and bath, permits — and we put the full scope in writing so you know exactly what's covered before work starts.
We write scope in plain terms: what we'll do, the materials, the sequence, and how any surprises are handled if something is uncovered.
How much does a detached ADU (DADU) build cost in Seattle?
Most detached ADU (DADU) build projects in Seattle fall between $207,000 – $517,500, 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 Seattle homeowners choose Xion Build
Transparent, written estimates with no hidden fees — you know what you're paying for before work begins.
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.
Our Seattle adus & conversions process
Each phase is inspected and documented, and we keep you updated so you always know what's happening and what's next.
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.
Frequently asked questions
Do you handle permits and inspections?
Yes. We manage permit applications, schedule inspections, and coordinate any required engineering so the work passes cleanly in Seattle.
Do you offer free estimates for detached ADU (DADU) build near Seattle?
Absolutely. We provide free, no-obligation in-home estimates throughout Seattle 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 long does a detached ADU (DADU) build take?
Timelines depend on scope and permitting. Once the plan is confirmed we give you a realistic schedule and keep you updated as the adus & conversions work progresses.
What should we decide before starting a detached ADU (DADU) 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 Seattle.
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