Basement finishing · Mercer Island, WA
Basement Bathroom Addition in Mercer Island, WA
Add a bath with proper plumbing and ejector if needed.
Basement Bathroom Addition in Mercer Island, WA
Looking for basement bathroom addition 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. Add a bath with proper plumbing and ejector if needed.
Mercer Island projects often involve sloped lots, shoreline rules, and mid-century homes that benefit from thoughtful structural and design planning.
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 basement bathroom addition
A typical basement bathroom addition in Mercer Island can involve electrical, finishes, insulation, framing — 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 a basement bathroom addition cost in Mercer Island?
Most basement bathroom addition projects in Mercer Island fall between $50,500 – $126,000, 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
Local crews who know Eastside permitting, inspections, and the way Pacific Northwest weather tests a home.
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 Mercer Island basement finishing process
It starts with a free, no-obligation consultation: what you want, the constraints, and a realistic budget range before you commit to anything.
We pull the permits, schedule every trade in the right order, and protect your home, landscaping, and daily routine throughout the build.
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 offer a basement bathroom addition in Mercer Island, WA?
Yes. Add a bath with proper plumbing and ejector if needed. Xion Build is a licensed, bonded, and insured basement finishing contractor serving Mercer Island and the surrounding WA communities.
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.
Do you offer free estimates for basement bathroom addition near Mercer Island?
Absolutely. We provide free, no-obligation in-home estimates throughout Mercer Island and the greater Eastside, with transparent, itemized pricing.
How much does a basement bathroom addition cost in Mercer Island?
Most basement bathroom addition projects in Mercer Island run $50,500 – $126,000, 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.
What should we decide before starting a basement bathroom addition?
Your budget range, must-haves, timeline, and any finishes you already love. For basement finishing work we also review access, existing conditions, and whether permits are required in Mercer Island.
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