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
This is the physical process of building a secondary unit, which requires coordinating contractors, electricians, and plumbers. You need professional construction services when you are ready to break ground on your design. Costs are driven by the complexity of the foundation, interior finish levels, and site grading requirements. Exact pricing confirmed free on the call.
Frequently asked in Berkeley
Where can I find an ADU near me in Berkeley?
How do I find an ADU company in Berkeley?
What constitutes an emergency ADU situation?
Can I get an ADU quote in Berkeley?
Are there 24-hour ADU services available in Berkeley?
What is involved in accessory dwelling unit construction in Berkeley?
Are there prefab ADU options in Berkeley?
Also serving nearby: Richmond · Oakland · Daly City · Vallejo · Concord
More on this: HUD ADU resources — ADU policy and financing research.
Service area details
Serving all of Berkeley — population 118,962; about 11,403 residents per square mile across 10.4 sq mi. ZIP codes covered include 94701, 94702, 94703, 94704, 94705, 94707, 94708, 94709.
Neighborhoods served in Berkeley: Gourmet Ghetto, Elmwood, South Berkeley, North Berkeley, Ocean View — and every surrounding area.
Areas we serve
Browse by state, then city.
