What does accessory dwelling unit mean

Looking for what does accessory dwelling unit mean 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

An accessory dwelling unit is a secondary house or apartment that shares the building lot of a larger, primary home. It is a flexible housing solution used for aging parents, adult children, or generating rental income. The term covers everything from garage conversions to new detached cottages. Understanding this definition helps you determine if your property has the potential to add living space. Exact pricing confirmed free on the call.

Frequently asked in San Francisco

What are the most common reasons people build local ADUs in San Francisco?

Local ADUs in San Francisco are frequently built for multi-generational living, allowing family members to live independently on the same property. They are also a popular choice for generating rental income to help offset property costs. Some homeowners build them for home offices or studios. Each purpose has unique design considerations.

How do I get an ADU quote in San Francisco?

What does ADU construction involve in San Francisco?

ADU construction in San Francisco begins with design and obtaining necessary permits from the city. This is followed by site preparation, foundation work, and framing. Utility connections, insulation, and exterior finishing come next. The interior is then completed, followed by final inspections. Experienced crews manage each phase.

Who are the best ADU builders in the San Francisco area?

The best ADU builders in San Francisco have a strong understanding of local building codes and permitting processes. They possess a good portfolio of completed projects and receive positive feedback from clients. We help you identify such experienced professionals for your project.

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

Getting an ADU permit in San Francisco involves submitting detailed architectural plans and site surveys to the city planning department. These plans must comply with all zoning regulations and building codes. A professional designer or architect can greatly assist with this complex process. We help you find those experts.

What are the typical costs associated with ADU construction in San Francisco?

The costs associated with ADU construction in San Francisco depend on many variables. These include the size of the unit, the materials selected, and any site-specific challenges like steep slopes or difficult access. A professional estimate is the best way to understand the financial scope for your project.

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

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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: Mission District, Pacific Heights, Sunset District, Richmond District, Noe Valley — and every surrounding area.