Looking for accessory dwelling unit companies in San Jose, CA? Call AccessoryDwellingUnit Direct for a contact a provider — no obligation. Licensed adu builders serve San Jose 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 involves variables that shift your total investment. The footprint size and complexity of the architectural design are primary factors. Are you planning a detached unit that requires new utility trenching, or is this a garage conversion that uses existing plumbing? Site accessibility, soil conditions, and your choice of finishes—like luxury flooring versus standard options—also play significant roles. Permitting fees vary widely depending on your local municipality and current zoning requirements. Exact pricing confirmed free on the call.

About this service

ADU companies provide end-to-end solutions, often integrating design, permitting, and construction under one roof. You need to engage a company when you want a streamlined experience and want to avoid the stress of hiring separate architects and builders. These companies handle the coordination of the entire project, ensuring that every phase of development transitions smoothly while keeping you updated on the progress and budget status of your new unit.

Frequently asked in San Jose

What are the disadvantages of ADUs?

Potential drawbacks can include initial construction costs and impacts on existing utility services. It's also important to consider local zoning ordinances and any potential neighborhood concerns. A qualified professional can help you weigh these factors against the advantages for your specific San Jose property.

How much does an ADU cost in California?

The cost of an ADU in California, including San Jose, varies significantly based on size, materials, and site complexity. Factors like foundation type, finishes, and necessary utility upgrades all play a role. Getting a custom quote from a local expert is the best way to understand the investment for your unique situation.

What are the rules for ADUs in California?

California has statewide ADU laws designed to streamline approvals, but local jurisdictions like San Jose may have additional specific requirements. These often involve setbacks, lot coverage limits, and parking regulations. Understanding these nuances is crucial for a smooth project.

Is ADU allowed in Maryland?

What are the rules for ADU in California?

While various grant programs have existed or are being explored in California to incentivize ADU development, specific details and availability can change. It's best to speak with a local ADU professional in San Jose who stays updated on current financial incentives and requirements.

Also serving nearby: Burbank · Santa Clara · Sunnyvale · Fremont · Hayward

All cities in California →

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

Service area details

969,655residents

5,449per sq mile

8ZIP codes served

Serving all of San Jose — population 969,655; about 5,449 residents per square mile across 177.9 sq mi. ZIP codes covered include 95025, 95101, 95103, 95106, 95108, 95109, 95110, 95111.

Neighborhoods served in San Jose: Willow Glen, Almaden Valley, Japantown, Rose Garden, Berryessa — and every surrounding area.