ADUs & conversions · Issaquah, WA
Basement ADU Conversion in Issaquah, WA
Turn a basement into a separate-entry dwelling unit.
Basement ADU Conversion in Issaquah, WA
Xion Build provides expert basement ADU conversion in Issaquah. As a trusted Issaquah 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.
Issaquah's Highlands and older in-town homes alike benefit from energy-smart upgrades and remodels that respect the surrounding terrain.
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 Issaquah can involve permits, foundation, utilities, finishes — 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 Issaquah?
Most basement ADU conversion projects in Issaquah 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 Issaquah homeowners choose Xion Build
One dedicated point of contact coordinates the entire job, so you're never chasing subcontractors or wondering who's responsible.
Local crews who know Eastside permitting, inspections, and the way Pacific Northwest weather tests a home.
Transparent, written estimates with no hidden fees — you know what you're paying for before work begins.
Our Issaquah adus & conversions process
Design and material selections come next, so finishes, fixtures, and pricing are locked in before demolition — no surprises mid-project.
We pull the permits, schedule every trade in the right order, and protect your home, landscaping, and daily routine throughout the build.
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
What should we decide before starting a basement ADU conversion?
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 Issaquah.
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.
Do you handle permits and inspections?
Yes. We manage permit applications, schedule inspections, and coordinate any required engineering so the work passes cleanly in Issaquah.
How much does a basement ADU conversion cost in Issaquah?
Most basement ADU conversion projects in Issaquah run $100,500 – $225,500, depending on scope, finishes, and existing conditions. After a free in-home consultation we provide a detailed written estimate so your Issaquah price reflects the actual project — not a guess.
Do you offer a basement ADU conversion in Issaquah, WA?
Yes. Turn a basement into a separate-entry dwelling unit. Xion Build is a licensed, bonded, and insured adus & conversions contractor serving Issaquah and the surrounding WA communities.
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