Basement ADU Conversion in Mill Creek, WA

Basement ADU Conversion in Mill Creek, WA

Xion Build provides expert basement ADU conversion in Mill Creek. As a trusted Mill Creek adus & conversions contractor, we manage design, materials, permits, and every trade in-house so your project stays on schedule and on budget. Turn a basement into a separate-entry dwelling unit.

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

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 basement ADU conversion

A typical basement ADU conversion in Mill Creek can involve framing, permits, utilities, the kitchen and bath — 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 basement ADU conversion cost in Mill Creek?

Most basement ADU conversion projects in Mill Creek fall between $100,500 – $225,500, 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

One dedicated point of contact coordinates the entire job, so you're never chasing subcontractors or wondering who's responsible.

Transparent, written estimates with no hidden fees — you know what you're paying for before work begins.

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

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.

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

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

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