Accessory Dwelling Units (ADUs)

General Information

Accessory dwelling units — also called ADUs, secondary units, or granny flats — are small living units, including a kitchen and bathroom, on properties zoned residential with a single-family home, duplex home, or multifamily building in place. Junior Accessory Dwelling Units (JADUs) are small (less than 500 square feet) that must be within the existing square footage of a single-family home.

As of January 2020, ADUs and JADUs can be built on most residential properties in California. The information provided here summarizes the benefits for ADUs, provides links to standards, and answers the most frequently asked questions about where, how, and how much can be built as an ADU or JADU.

Benefits

There are many benefits to ADUs and JADUs, including that they...  

  • Create more affordable housing for our community and families; 
  • Provide an income opportunity for homeowners; 
  • Promote infill development; and 
  • Encourage the use of public transportation. 

Local Ordinance and Efforts

In July 2025, the City of Watsonville updated the City's ADU Ordinance in accordance with state legislation pertaining to ADUS, and is codified in Chapter 14-23 of the Zoning Code (Title 14).

The City is taking steps to implement the recently adopted “6th Cycle” Housing Element. In July, the City Council took action to amend the Municipal Code to address current state law regarding ADUs and JADUs. As part of this effort, the Community Development Department also prepared a handout to better explain ADUs and to serve as a user guide to determine which ADU best suits your needs and property. Click here to download a copy of the handout and learn more about the different types of ADUs, along with associated regulations and design considerations.

In addition, the following links provide information helpful in preparing an Building Permit application and provide answers to frequently asked question: 

State Legislation and Materials

If you're interested in further information about state legislation on ADUs — what’s allowed and where — see the California Department of Housing and Community Development’s new Accessory Dwelling Unit Handbook.  

Contact Information  

For general information and to ask questions about ADUs:   

  • Call: (831) 768-3050
  • Email: cdd@cityofwatsonville.org

We can help answer questions ranging from constructing a new ADU to legalizing an existing, unpermitted ADU.

Resources