Accessory dwelling unit construction

Looking for accessory dwelling unit construction in San Francisco, CA? Call AccessoryDwellingUnit Experts for a contact a provider — no obligation. Licensed adu builders serve San Francisco and the surrounding area, and you'll get straight answers on timing and what affects the price.

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 San Francisco

What is the permit process for an ADU in San Francisco?

The permit process for an ADU in San Francisco involves submitting detailed architectural plans and engineering documents to the city's planning department. You'll need to ensure compliance with zoning laws, building codes, and specific ADU ordinances. This can be a complex process, and working with experienced professionals is highly recommended.

How can I get a quote for an ADU in San Francisco?

To get a quote for an ADU in San Francisco, make one quick call to our service. We will arrange for a specialist to assess your property and discuss your project needs. This allows us to provide an accurate, no-obligation estimate. It's the most direct way to understand the investment required for your accessory dwelling unit.

Are there specific rules for backyard ADUs in San Francisco?

Yes, San Francisco has specific regulations for backyard ADUs, often referred to as 'Accessory Dwelling Units'. These rules typically cover lot coverage, setbacks from property lines, and height restrictions. It's essential to review the city's planning code or consult with an ADU professional to ensure your plans comply.

What factors influence the cost of building an ADU in San Francisco?

The cost of building an ADU in San Francisco is influenced by several factors, including the size and complexity of the design. Material choices for finishes, the need for utility upgrades, and site preparation requirements also play a role. The specific location within the city can also affect costs due to varying site conditions.

How do I find an ADU contractor in San Francisco?

Can I get a quote for a prefabricated ADU in San Francisco?

What are the benefits of adding an in-law suite to my San Francisco home?

Adding an in-law suite, or ADU, to your San Francisco home offers benefits like increased rental income potential and added living space for family members. It can also enhance your property's value. These units provide a flexible solution for multi-generational living or for accommodating guests.

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

808,988residents

17,323per sq mile

8ZIP codes served

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: The Castro, Nob Hill, Pacific Heights, The Richmond District, The Sunset District, Haight-Ashbury — and every surrounding area.