Why this article is important: While ADUs have taken hold across the state, the Coastal Commission has largely succeeded in preventing ADUs to take root along the coast. Following the 2025 LA wildfires, a new law is wresting control from the Coastal Commission on ADUs, expanding their use as a solution for homeowners seeking to rebuild from the disaster.
Coastal ADU laws
Accessory dwelling units (ADUs) have been the focus of numerous legislative treatments in recent years, all to expand their availability for California homeowners and alleviate the housing shortage.
A new law, passed by Assembly Bill 462, now requires swifter approval or rejection of coastal development permits for ADUs and removes hurdles to building an ADU on an empty lot following a natural disaster.
Typically, owners of housing located in coastal zones — within 1,000 yards of the coast — are not granted the same streamlined, 60-day permitting process for ADUs as housing located elsewhere in the state. In fact, the new law’s legal analysis claims the usual permitting timeframe for ADUs located in a coastal zone is years. That’s because local coastal programs, overseen by the California Coastal Commission and local governments, may create their own approval processes to approving development, including ADUs.
As a result, housing located near the coast is subject to greater permitting costs and a longer permitting process (when they are granted permits at all), for regular housing and ADUs alike.
The law requires local governments and the California Coastal Commission to approve or reject an ADU application within 60 days of receiving a complete application. [Calif. Government Code §66329(a)]
When the Commission does not issue a decision within 60 days, the permit will be deemed approved. [Gov C §66329(b)(5)]
The change follows steps by the Coastal Commission to prevent residential rebuilding after Los Angeles County’s devastating wildfires of early 2025.
Related article:
Mortgage forbearance for homeowners affected by 2025 wildfires
ADUs without a primary dwelling
California law does not allow a certificate of occupancy to be issued for an ADU unless a certificate of occupancy has first been issued for the property’s primary dwelling. [Gov C §66328(a)]
However, the new law creates an exception: a certificate of occupancy may be issued for an ADU (that is not attached to the primary dwelling) when a proclamation of a state of emergency has been made by the Governor on or after February 1, 2025, and:
- the primary dwelling has been substantially damaged or destroyed as a result of the state of emergency; and
- the ADU has been issued construction permits and passed all inspection requirements. [Gov C §66328(b); (c)]
This change is an acknowledgement by legislatures that ADUs can serve as transitional housing following an emergency. An ADU affords the homeowner a place to live while the more lengthy permitting and construction process continues for an owner’s primary residence.
Related article:
