Accessory dwelling unit construction cost — Gilbert, AZ

Last updated: September 24, 2026

What affects the price

Building an ADU is a major project, and the final bill depends on a few key things. Site prep is a big factor; if your land is sloped or needs extensive utility connections, costs go up. The materials you choose—from siding to kitchen finishes—also change the math significantly. Whether you’re building a detached unit or converting an existing garage shifts the permit requirements and structural work needed. We provide exact pricing confirmed free on the call.

About this service

The cost to build an ADU varies based on whether you are converting an existing garage or building a new detached structure from the ground up. Factors like foundation work, utility extensions, high-end finishes, and site access all influence the final total. Exact pricing confirmed free on the call.

Frequently asked in Gilbert

Also serving nearby: Chandler · Mesa · Tempe · Phoenix · Scottsdale

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More on this: HUD ADU resources — ADU policy and financing research.

Service area details

Serving all of Gilbert — population 275,411; about 4,011 residents per square mile across 68.7 sq mi. ZIP codes covered include 85233, 85234, 85295, 85296, 85297, 85298, 85299.

Neighborhoods served in Gilbert: Power Ranch, Windsor Creek, Cooper Commons, Higley Park, Villages at Power Ranch — and every surrounding area.