Home additions · Mercer Island, WA
Home Office Addition in Mercer Island, WA
A quiet, code-built dedicated workspace with proper electrical.
Home Office Addition in Mercer Island, WA
Xion Build provides expert home office addition in Mercer Island. As a trusted Mercer Island home additions contractor, we manage design, materials, permits, and every trade in-house so your project stays on schedule and on budget. A quiet, code-built dedicated workspace with proper electrical.
Mercer Island projects often involve sloped lots, shoreline rules, and mid-century homes that benefit from thoughtful structural and design planning.
A home addition lives or dies on the connection to the existing house — foundation, framing, and rooflines have to marry seamlessly so the new space feels original.
What's included in your home office addition
A typical home office addition in Mercer Island can involve insulation, finishes, windows, framing — and we put the full scope in writing so you know exactly what's covered before work starts.
From room additions and bump-outs to second stories and full primary suites, we handle structural engineering and permits up front so there are no surprises.
How much does a home office addition cost in Mercer Island?
Most home office addition projects in Mercer Island fall between $51,000 – $153,000, 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 home additions project — so there are no surprises later.
Why Mercer Island homeowners choose Xion Build
Honest guidance on where to invest and where to save, so your budget goes toward what adds real, lasting value.
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.
Our Mercer Island home additions 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.
It starts with a free, no-obligation consultation: what you want, the constraints, and a realistic budget range before you commit to anything.
Frequently asked questions
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.
How much does a home office addition cost in Mercer Island?
Most home office addition projects in Mercer Island run $51,000 – $153,000, 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.
How long does a home office addition take?
Timelines depend on scope and permitting. Once the plan is confirmed we give you a realistic schedule and keep you updated as the home additions work progresses.
Are you a licensed home additions 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 a home office addition in Mercer Island, WA?
Yes. A quiet, code-built dedicated workspace with proper electrical. Xion Build is a licensed, bonded, and insured home additions contractor serving Mercer Island and the surrounding WA communities.
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