ADUs & conversions · Bellevue, WA

ADU Design & Permitting in Bellevue, WA

Plans and permits navigating local ADU rules.

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ADU Design & Permitting in Bellevue, WA

Xion Build provides expert ADU design & permitting in Bellevue. As a trusted Bellevue adus & conversions contractor, we manage design, materials, permits, and every trade in-house so your project stays on schedule and on budget. Plans and permits navigating local ADU rules.

From Bridle Trails to West Bellevue, Bellevue homeowners invest in kitchens, baths, and additions that match a high bar for finish quality and durability.

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 ADU design & permitting

A typical ADU design & permitting in Bellevue can involve the kitchen and bath, permits, framing, foundation — 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 an ADU design & permitting cost in Bellevue?

Most ADU design & permitting projects in Bellevue fall between $95,500 – $215,500, 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 adus & conversions project — so there are no surprises later.

Why Bellevue homeowners choose Xion Build

Licensed, bonded, and insured in Washington — every project is built to meet or exceed code and backed by a written warranty.

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 Bellevue adus & conversions process

Design and material selections come next, so finishes, fixtures, and pricing are locked in before demolition — no surprises mid-project.

Each phase is inspected and documented, and we keep you updated so you always know what's happening and what's next.

Handoff includes a detailed walkthrough and a written warranty — not a crew that vanishes the moment the dust settles.

Frequently asked questions

How much does an ADU design & permitting cost in Bellevue?

Most ADU design & permitting projects in Bellevue run $95,500 – $215,500, depending on scope, finishes, and existing conditions. After a free in-home consultation we provide a detailed written estimate so your Bellevue price reflects the actual project — not a guess.

Are you a licensed adus & conversions 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 Bellevue.

What should we decide before starting an ADU design & permitting?

Your budget range, must-haves, timeline, and any finishes you already love. For adus & conversions work we also review access, existing conditions, and whether permits are required in Bellevue.

Do you offer an ADU design & permitting in Bellevue, WA?

Yes. Plans and permits navigating local ADU rules. Xion Build is a licensed, bonded, and insured adus & conversions contractor serving Bellevue and the surrounding WA communities.

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