Cost of Accessory Dwelling Unit in Modesto, CA | AccessoryDwellingUnit Experts

Looking for cost of accessory dwelling unit in Modesto, CA? Call AccessoryDwellingUnit Experts 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 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

Building an ADU involves several variables that influence the total investment, including your local site conditions, utility hookups, and the finishes you select for the interior. We focus on transparency throughout your project planning to keep you on budget. Exact pricing confirmed free on the call.

Frequently asked in Modesto

What are the disadvantages of ADUs in Modesto?

The primary disadvantages of ADUs include the upfront construction costs and ensuring your property meets Modesto's zoning requirements for size and placement. You’ll also need to consider ongoing maintenance. Weighing these against the benefits of increased living space and rental income is important.

How much does an ADU cost in California?

What are the rules for ADUs in California?

California state law provides guidelines for ADUs, aiming to simplify their approval. However, cities like Modesto also have their own zoning ordinances that address details such as setbacks, lot coverage, and parking. We can help you navigate these requirements.

Is an ADU allowed in California?

Yes, Accessory Dwelling Units are widely permitted across California, thanks to state legislation designed to increase housing options. Most cities, including Modesto, have adopted ordinances to allow for ADUs. We can confirm the specifics for your location.

While California has offered grant programs to incentivize ADU development, these can vary and have specific eligibility criteria. It's essential to research current programs. We can provide information on potential financial assistance options available for ADUs.

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, Keyes, Empire, Ceres — and every surrounding area.