Looking for cost of accessory dwelling unit in Modesto, CA? Call AccessoryDwellingUnit Solutions 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 involves several moving parts that shape your total budget. The biggest factor is whether you choose a prefabricated unit or a custom build on-site. Site preparation is also significant; if your land requires extensive grading, utility trenching, or foundation work, costs will climb. Your choice of finishes—like kitchen cabinetry, flooring, and siding materials—also shifts the bottom line. We help you navigate these variables to find a setup that fits your property. Exact pricing confirmed free on the call.

About this service

The total price for an ADU depends on several moving parts, including the square footage, your foundation type, and local labor rates. Choosing high-end finishes or complex site prep will naturally increase the budget, while standard layouts help keep things manageable. Exact pricing confirmed free on the call.

Frequently asked in Modesto

What are the disadvantages of ADUs in Modesto?

Potential disadvantages can include the initial construction costs and the need for any necessary upgrades to your home's existing utility services. If the ADU is intended for rent, managing tenants is also a factor to consider. The pros can help you weigh these pros and cons for your Modesto property.

How much does an ADU cost in California?

What are the rules for ADUs in California?

Is an ADU allowed in Maryland?

Our services are focused on California cities like Modesto. For information on ADU regulations in Maryland, you will need to consult local resources specific to that state. Each region has its own unique set of rules and allowances for accessory dwelling units.

What are the rules for ADU in California?

California's ADU legislation provides a framework, but cities like Modesto may have their own specific local ordinances. These can address aspects such as lot coverage, design standards, and how ADUs integrate with existing infrastructure. The professionals you speak with will be well-versed in these.

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, North Modesto, West Modesto, Salida, Keyes — and every surrounding area.