Important ADU Law Changes for California Homeowners in 2025

If you're a homeowner planning to build or legalize an accessory dwelling unit (ADU) on your property, new California laws starting in 2025 could directly impact your project.

Governor Newsom has signed three new ADU bills that aim to simplify permitting, expand ADU options, and provide more clarity for ADU development in coastal areas.

Grover Beach ADU plan example

Here’s what you need to know:

Key Changes for ADU Projects in 2025

1. Legalizing Unpermitted ADUs (AB 2533)

   • ADUs or JADUs built before January 1, 2020, may now be legalized even if they don’t meet local codes, provided they meet essential health and safety standards.

   • New public notification rules will clarify what homeowners need to do for compliance.

2. Parking and Multifamily ADUs (SB 1211)

   • No replacement parking will be required, even for uncovered parking spaces converted to ADUs.

   • Multifamily properties can now have up to eight detached ADUs, significantly increasing development options for property owners.

3. Coastal Zone Guidance (SB 1077)

   • Homeowners in coastal areas will benefit from new, clearer guidelines for ADUs by July 1, 2026, with a public workshop allowing for feedback on the new rules.

What Does This Mean for You?

• If your local ordinance doesn't align with these new state rules by January 1, 2025, it will become null and void.

• Cities and counties across California will need to update their ADU policies, so it's a good time to plan or revisit your ADU project.

Stay ahead of these changes to make the most of the expanded ADU opportunities. Whether you're thinking of legalizing an existing unit or building a new one, these laws can simplify the process and increase your options.

For more detailed information, contact your local planning department or a real estate expert familiar with the latest ADU regulations.