ADU
Also known as: Accessory Dwelling Unit, Granny Flat, In-Law Unit
An Accessory Dwelling Unit (ADU) is a secondary residential unit built on an existing single-family or multifamily residential lot. California law, particularly Government Code Sections 65852.2 and 65852.22, has aggressively expanded ADU rights as part of the state's strategy to address the housing crisis, and has significantly preempted HOA authority to restrict ADU construction. Under current law, HOAs cannot prohibit ADUs on lots zoned for residential use where local zoning allows them. An association may impose reasonable architectural standards on ADUs — such as requirements related to design, materials, and landscaping — but only if those standards do not unreasonably increase the cost of building the ADU, effectively prohibit its construction, or conflict with state ADU law. Any CC&R provision that outright bans ADUs is void and unenforceable. California recognizes several ADU types: attached ADUs built as additions to the primary dwelling, detached ADUs as standalone structures, junior ADUs (JADUs) of 500 square feet or less created within the existing footprint of the primary dwelling, and converted ADUs in existing accessory structures such as garages. For HOA boards, the practical implications include updating architectural guidelines to permit ADU applications, establishing a streamlined review process that does not impose conditions beyond what state law allows, and addressing community concerns about parking, aesthetics, and density within the bounds of the law. The state has continued to expand ADU rights through subsequent legislation, and boards should consult with their association attorney to ensure current compliance.
Example in Context
A homeowner submitted plans to build a 600-square-foot detached ADU in her backyard. Although the CC&Rs prohibited accessory structures, the board's attorney advised that state ADU law preempted the restriction, so the architectural committee reviewed the application solely for compliance with the community's reasonable design standards.
Frequently Asked Questions
Can our HOA deny an ADU application if the CC&Rs prohibit accessory structures?
No. California state law preempts CC&R provisions that effectively prohibit ADUs. Even if the governing documents ban accessory structures, detached buildings, or secondary dwellings, those provisions are unenforceable to the extent they conflict with state ADU law. The HOA may impose reasonable design standards — such as requiring matching exterior materials — but cannot deny the application outright or impose conditions that make construction infeasible.