Home additions · Seattle, WA
Room Addition in Seattle, WA
Add a bedroom, office, or living space tied seamlessly into the home.
Room Addition in Seattle, WA
Xion Build provides expert room addition in Seattle. As a trusted Seattle home additions contractor, we manage design, materials, permits, and every trade in-house so your project stays on schedule and on budget. Add a bedroom, office, or living space tied seamlessly into the home.
From Laurelhurst to Queen Anne, Seattle's older homes often need structural care alongside the kitchen, bath, and addition work that modernizes them.
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 room addition
A typical room addition in Seattle can involve windows, insulation, foundation work, roofline tie-in — 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 room addition cost in Seattle?
Most room addition projects in Seattle fall between $69,000 – $230,000, 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 Seattle homeowners choose Xion Build
One dedicated point of contact coordinates the entire job, so you're never chasing subcontractors or wondering who's responsible.
Local crews who know Eastside permitting, inspections, and the way Pacific Northwest weather tests a home.
Transparent, written estimates with no hidden fees — you know what you're paying for before work begins.
Our Seattle home additions process
Handoff includes a detailed walkthrough and a written warranty — not a crew that vanishes the moment the dust settles.
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
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.
How much does a room addition cost in Seattle?
Most room addition projects in Seattle run $69,000 – $230,000, depending on scope, finishes, and existing conditions. After a free in-home consultation we provide a detailed written estimate so your Seattle price reflects the actual project — not a guess.
What should we decide before starting a 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 Seattle.
Do you offer free estimates for room addition near Seattle?
Absolutely. We provide free, no-obligation in-home estimates throughout Seattle and the greater Eastside, with transparent, itemized pricing.
Do you offer a room addition in Seattle, WA?
Yes. Add a bedroom, office, or living space tied seamlessly into the home. Xion Build is a licensed, bonded, and insured home additions contractor serving Seattle and the surrounding WA communities.
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