Hero section image

Prefab ADU in Contra Costa County

Abodu makes and installs prefab homes for play, passive income and possibility in as little as 6 months.

About Contra Costa County

Contra Costa County offers a perfect blend of vibrant urban amenities, scenic landscapes, and a diverse community, making it an ideal place to enjoy both city life and outdoor adventures. Due to California’s housing crunch, there’s been increasing interest in Accessory Dwelling Units (ADUs), commonly known as granny flats, in-law units, or backyard cottages. ADUs provide a unique opportunity for homeowners to maximize their property value while creating additional housing options.

What are the benefits of having an ADU?

ADUs offer several advantages for homeowners. They can provide additional rental income, accommodate family members, increase property value, and contribute to the community by addressing housing shortages. Moreover, as prefab units are constructed off-site and delivered ready to be installed, they promise a faster, more efficient, and less disruptive building process compared to traditional construction methods.

An Abodu One being installed by a crane.

An Abodu One being installed by a crane.

Contra Costa County ADU requirements

When planning to build a prefab ADU in Contra Costa County, you must adhere to specific requirements. The Conservation & Development Department is the best place to learn about Contra Costa County ADU requirements.


How much does an ADU cost in Contra Costa County?

The cost varies depending on several factors, including the type of construction (new or modifying an existing structure), size of the unit, and materials selected.

Building Permits

How do I get an ADU permit in Contra Costa County?

The permitting process for building an ADU requires submitting detailed plans and documentation—such as floor plans, energy calculations, and engineering data—for review. The application for a new building permit is 100% digital and can be submitted online through the ePermits Center.


What are the top ADU requirements in Contra Costa County?

Since ADUs are functional living spaces separate from the primary residence, California law requires secondary units to have access to basic utilities like water, sewage, and electricity. In addition, each city within Contra Costa County may have specific requirements for ADUs like setbacks and off-street parking.


How do I finance an ADU in Contra Costa County?

You can finance prefab ADU projects through various channels, including home equity loans, personal loans, or savings. Some prefab ADU companies also offer financing solutions, making the process easier for homeowners.

FAQs: Prefab ADUs in Contra Costa County

Fee schedules for ADU permits in Contra Costa County vary by city and unit size, but you can expect to pay a few thousand dollars. Find more information on your city's permitting page. Our Abodu Project Managers handle the permitting process for all prefab ADU builds.

California state law mandates a minimum distance of 4 feet between the ADU and a homeowner’s property line.

Maximum size allowed for most ADUs in Contra Costa County is 1,000 square feet except for in certain districts. Check the current ordinance code for the most up-to-date information.

ADUs usually come equipped with several essential appliances, including, but not limited to:

  • Stove or cooktop

  • Refrigerator

  • Oven

  • Dishwasher

  • Washer and dryer

  • Water heater

  • HVAC system

Whether you’re in Concord, Danville, El Cerrito, Hercules, Lafayette, Orinda, Pleasant Hill, Richmond, San Ramon or Walnut Creek, Abodu is ready to help you navigate the process of adding a beautiful, functional ADU to your home.

Get your backyard assessment.

Upgrade your property with a custom prefab ADU by Abodu. We off full end-to-end service, including permitting, site work, construction, and delivery. Schedule a call or visit our showroom today.

A crane installing an Abodu.
First Name
Last Name
Where is your Abodu going?
Additional Comments

By submitting your information, you consent to receive communication from Abodu via email and/or text. You can opt out at anytime.

We'll handle the permits.

Delivered in as little as 6 months.

No hassle installation.

Expand your home’s value and livable space.

Find your new Abodu.

Image alt text

Book a call or tour today.