Home additions · Mercer Island, WA
Great Room Addition in Mercer Island, WA
A large open living and entertaining space.
Great Room Addition in Mercer Island, WA
When Mercer Island homeowners search for great room addition or a dependable home additions contractor near them, they want craftsmanship that lasts and a crew that communicates. That's exactly what we do. A large open living and entertaining space.
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 great room addition
A typical great room addition in Mercer Island can involve foundation work, framing, insulation, finishes — 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 great room addition cost in Mercer Island?
Most great room addition projects in Mercer Island fall between $165,500 – $482,500, 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 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.
One dedicated point of contact coordinates the entire job, so you're never chasing subcontractors or wondering who's responsible.
Meticulous job sites and clear daily communication, with respect for your home, your time, and your neighbors.
Our Mercer Island home additions process
Design and material selections come next, so finishes, fixtures, and pricing are locked in before demolition — no surprises mid-project.
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.
Frequently asked questions
Do you offer free estimates for great room addition near Mercer Island?
Absolutely. We provide free, no-obligation in-home estimates throughout Mercer Island and the greater Eastside, with transparent, itemized pricing.
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 great room addition in Mercer Island, WA?
Yes. A large open living and entertaining space. Xion Build is a licensed, bonded, and insured home additions contractor serving Mercer Island and the surrounding WA communities.
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.
What should we decide before starting a great room addition?
Your budget range, must-haves, timeline, and any finishes you already love. For home additions work we also review access, existing conditions, and whether permits are required in Mercer Island.
Related services in Mercer Island
Dining room expansion
Expand or add a formal dining space for gatherings.
View detailsAddition design & engineering
Architectural plans and structural engineering for additions.
View detailsSunroom & four-season room
Insulated, conditioned sunrooms usable year-round.
View detailsPrimary suite addition
A new primary bedroom, bath, and closet wing.
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