Basement finishing · Mercer Island, WA
Full Basement Finishing in Mercer Island, WA
Frame, insulate, and finish a basement into living space.
Full Basement Finishing in Mercer Island, WA
Looking for full basement finishing in Mercer Island? Xion Build is a licensed, bonded, and insured basement finishing contractor delivering standout results for Mercer Island homeowners — start to finish, under one roof. Frame, insulate, and finish a basement into living space.
Mercer Island projects often involve sloped lots, shoreline rules, and mid-century homes that benefit from thoughtful structural and design planning.
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 full basement finishing
A typical full basement finishing in Mercer Island can involve egress, finishes, framing, electrical — 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 full basement finishing cost in Mercer Island?
Most full basement finishing projects in Mercer Island fall between $32,500 – $117,000, 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 basement finishing project — so there are no surprises later.
Why Mercer Island homeowners choose Xion Build
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.
Local crews who know Eastside permitting, inspections, and the way Pacific Northwest weather tests a home.
Our Mercer Island basement finishing process
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.
Design and material selections come next, so finishes, fixtures, and pricing are locked in before demolition — no surprises mid-project.
Frequently asked questions
How long does a full basement finishing take?
Timelines depend on scope and permitting. Once the plan is confirmed we give you a realistic schedule and keep you updated as the basement finishing work progresses.
Are you a licensed basement finishing 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 a full basement finishing cost in Mercer Island?
Most full basement finishing projects in Mercer Island run $32,500 – $117,000, depending on scope, finishes, and existing conditions. After a free in-home consultation we provide a detailed written estimate so your Mercer Island price reflects the actual project — not a guess.
Do you handle permits and inspections?
Yes. We manage permit applications, schedule inspections, and coordinate any required engineering so the work passes cleanly in Mercer Island.
Do you offer a full basement finishing in Mercer Island, WA?
Yes. Frame, insulate, and finish a basement into living space. Xion Build is a licensed, bonded, and insured basement finishing contractor serving Mercer Island and the surrounding WA communities.
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