Basement finishing · Sammamish, WA
Basement Bathroom Addition in Sammamish, WA
Add a bath with proper plumbing and ejector if needed.
Basement Bathroom Addition in Sammamish, WA
Looking for basement bathroom addition in Sammamish? Xion Build is a licensed, bonded, and insured basement finishing contractor delivering standout results for Sammamish homeowners — start to finish, under one roof. Add a bath with proper plumbing and ejector if needed.
Sammamish plateau homes are often large and family-focused, where additions, kitchens, and outdoor living spaces deliver the most lasting value.
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 bathroom addition
A typical basement bathroom addition in Sammamish can involve insulation, framing, egress, 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 bathroom addition cost in Sammamish?
Most basement bathroom addition projects in Sammamish fall between $44,500 – $111,500, 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 basement finishing project — so there are no surprises later.
Why Sammamish homeowners choose Xion Build
Meticulous job sites and clear daily communication, with respect for your home, your time, and your neighbors.
Transparent, written estimates with no hidden fees — you know what you're paying for before work begins.
One dedicated point of contact coordinates the entire job, so you're never chasing subcontractors or wondering who's responsible.
Our Sammamish 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
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 handle permits and inspections?
Yes. We manage permit applications, schedule inspections, and coordinate any required engineering so the work passes cleanly in Sammamish.
How much does a basement bathroom addition cost in Sammamish?
Most basement bathroom addition projects in Sammamish run $44,500 – $111,500, depending on scope, finishes, and existing conditions. After a free in-home consultation we provide a detailed written estimate so your Sammamish price reflects the actual project — not a guess.
Do you offer a basement bathroom addition in Sammamish, WA?
Yes. Add a bath with proper plumbing and ejector if needed. Xion Build is a licensed, bonded, and insured basement finishing contractor serving Sammamish and the surrounding WA communities.
Do you offer free estimates for basement bathroom addition near Sammamish?
Absolutely. We provide free, no-obligation in-home estimates throughout Sammamish and the greater Eastside, with transparent, itemized pricing.
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