ADUs & conversions · Mill Creek, WA

Attached ADU Build in Mill Creek, WA

Attached accessory dwelling units within the home's footprint.

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Attached ADU Build in Mill Creek, WA

When Mill Creek homeowners search for attached ADU 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. Attached accessory dwelling units within the home's footprint.

Mill Creek's well-kept neighborhoods reward high-quality kitchen, bath, and outdoor-living upgrades that match the community's standard.

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 Mill Creek can involve framing, finishes, foundation, the kitchen and bath — 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 Mill Creek?

Most attached ADU build projects in Mill Creek fall between $174,000 – $522,500, 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 Mill Creek homeowners choose Xion Build

Meticulous job sites and clear daily communication, with respect for your home, your time, and your neighbors.

Licensed, bonded, and insured in Washington — every project is built to meet or exceed code and backed by a written warranty.

Honest guidance on where to invest and where to save, so your budget goes toward what adds real, lasting value.

Our Mill Creek adus & conversions process

We pull the permits, schedule every trade in the right order, and protect your home, landscaping, and daily routine throughout the build.

Handoff includes a detailed walkthrough and a written warranty — not a crew that vanishes the moment the dust settles.

It starts with a free, no-obligation consultation: what you want, the constraints, and a realistic budget range before you commit to anything.

Frequently asked questions

Do you offer free estimates for attached ADU build near Mill Creek?

Absolutely. We provide free, no-obligation in-home estimates throughout Mill Creek and the greater Eastside, with transparent, itemized pricing.

Do you handle permits and inspections?

Yes. We manage permit applications, schedule inspections, and coordinate any required engineering so the work passes cleanly in Mill Creek.

Do you offer an attached ADU build in Mill Creek, WA?

Yes. Attached accessory dwelling units within the home's footprint. Xion Build is a licensed, bonded, and insured adus & conversions contractor serving Mill Creek and the surrounding WA communities.

How much does an attached ADU build cost in Mill Creek?

Most attached ADU build projects in Mill Creek run $174,000 – $522,500, depending on scope, finishes, and existing conditions. After a free in-home consultation we provide a detailed written estimate so your Mill Creek price reflects the actual project — not a guess.

How long does an attached ADU 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.

Related services in Mill Creek

ADU design & permitting

Plans and permits navigating local ADU rules.

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Basement ADU conversion

Turn a basement into a separate-entry dwelling unit.

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Garage conversion to ADU

Convert a garage into a legal, livable ADU.

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Garage to living space

Convert a garage into a gym, office, or studio.

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