Accessory dwelling unit construction — Berkeley, CA
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 involves the physical building process, from laying the foundation to installing the roof and interior finishes. It covers the actual labor and materials needed to transform a design into a finished home. You need this service when you have your plans ready and are prepared to break ground. Costs are typically affected by square footage and interior materials chosen for the unit. Exact pricing confirmed free on the call.
Frequently asked in Berkeley
What are homes with in-law suites like?
What are accessory dwelling units (ADUs)?
What is a backyard accessory dwelling unit?
What does accessory dwelling unit mean?
Who is an ADU builder?
Where can I find accessory dwelling unit builders near me?
What is the cost to build an accessory dwelling unit?
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, West Berkeley, North Berkeley, South Berkeley, Downtown Berkeley — and every surrounding area.
Areas we serve
Browse by state, then city.