Adu builder — San Francisco, 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

An ADU builder is a professional who manages the design, permitting, and construction of your secondary unit. You need to hire one when you want a streamlined process that handles the heavy lifting from start to finish. Builders provide expertise on zoning and structural requirements that keep your project on budget. Exact pricing confirmed free on the call.

Frequently asked in San Francisco

Also serving nearby: Daly City · Richmond · San Mateo · Berkeley · Oakland

All cities in California →

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

Service area details

Serving all of San Francisco — population 808,988; about 17,323 residents per square mile across 46.7 sq mi. ZIP codes covered include 94102, 94103, 94104, 94105, 94107, 94108, 94109, 94110.

Neighborhoods served in San Francisco: Mission District, Haight-Ashbury, Pacific Heights, The Castro, Nob Hill, SoMa — and every surrounding area.