Accessory dwelling units and junior accessory dwelling units

The law broadens homeowners’ ability to add small housing units and prevents private property rules from blocking ADUs or junior ADUs on lots where single-family homes are allowed.

What the law does ​

• Requires local agencies to ministerially approve up to two detached new-construction ADUs on a lot with a proposed or existing single-family home, subject to specified size, height, and setback limits.
• Allows local agencies to limit each of those detached ADUs to 800 square feet of livable space and apply specified height limits.
• Does not require local agencies to approve a junior ADU on a lot where two detached new-construction ADUs have been built under this provision.
• Makes covenants, deed restrictions, and planned-development governing documents unenforceable when they effectively prohibit or unreasonably restrict an ADU or junior ADU on a lot zoned to allow single-family residential use.
• Continues to allow reasonable private restrictions that do not unreasonably raise construction costs, effectively bar construction, or eliminate the ability to build an eligible ADU or junior ADU.

Who it affects ​

• Owners of lots with proposed or existing single-family homes in residential or mixed-use zones.
• Homeowners associations, planned developments, and other private parties enforcing property restrictions.
• Local agencies reviewing ADU and junior ADU building-permit applications.