Looking for accessory dwelling unit contractor san diego in Modesto, CA? Call AccessoryDwellingUnit Pros for a contact a provider — no obligation. Licensed adu builders serve Modesto 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 custom project, so costs vary based on your specific choices. Site conditions are the biggest factor; if your land requires significant grading, utility extensions, or foundation work, those expenses add up quickly. Choosing high-end finishes, custom cabinetry, or complex roof lines will also push the budget higher compared to a standard design. Prefabricated units often offer predictable costs, while custom site-built structures allow for more flexibility but can be harder to estimate upfront. Exact pricing confirmed free on the call.

About this service

A San Diego-based contractor understands the specific seismic requirements, coastal commission rules, and local ordinances that govern backyard units in the region. You need a local specialist when your property is located within San Diego city or county limits to ensure your project complies with specific regional density mandates. These contractors are experts in navigating the unique permit process required by local authorities to get your project approved and completed correctly. Exact pricing confirmed free on the call.

Frequently asked in Modesto

What are the disadvantages of ADUs in Modesto?

Potential drawbacks include the initial investment and the fact that it will take up yard space. You'll also need to adhere to Modesto's specific zoning and building codes. The pros can thoroughly review these factors with you to ensure you're making an informed decision for your property.

How much does an ADU cost in California?

The cost of an ADU in California, including in Modesto, varies greatly depending on the unit's size, design complexity, and site-specific conditions. Factors like foundation work, utility connections, and the quality of finishes will impact the final price. A personalized quote from the pros will provide the most accurate estimate for your project.

What are the rules for ADUs in California?

Is an ADU allowed in Maryland?

This service is focused on ADU projects within California cities like Modesto. For ADUs in Maryland, you will need to find a contractor and service provider who is licensed and knowledgeable about Maryland's specific building codes and zoning laws. This team specializes in the Modesto area.

That specific grant program was established for California. While other states and localities may have different incentive programs or financing options for ADUs, they will not be the same as California's. When you call, inquire with the pros about any current financial assistance available for your Modesto ADU project.

Can I build an ADU on my property in Modesto?

Many properties in Modesto are suitable for ADUs, provided they meet the city's zoning and land use regulations. The pros will conduct a comprehensive site assessment to confirm your property's eligibility. They will address any potential challenges and guide you through the permitting and construction process.

Also serving nearby: Manteca · Tracy · Stockton · Merced · Antioch

All cities in California →

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

Service area details

218,915residents

5,049per sq mile

8ZIP codes served

Serving all of Modesto — population 218,915; about 5,049 residents per square mile across 43.4 sq mi. ZIP codes covered include 95350, 95351, 95352, 95353, 95354, 95355, 95356, 95357.

Neighborhoods served in Modesto: Downtown Modesto, Salida, Ceres, Keyes — and every surrounding area.