SB 543
ADU Clarity and Consistency
SB 543 clarifies and codifies existing guidance regarding ADUs and Junior ADUs (JADUs) from the Department of Housing and Community Development to accelerate the construction of these low-cost housing options.
ADUs and Junior ADUs are a relatively low cost way to add to the state’s housing supply, while adding value to existing homes and creating flexibility for growing and extended families. They are also the most popular form of new housing in the state, thanks primarily to new state laws that make them easier and faster to build.
However, some of these new laws contain provisions that are unclear, or are deliberately mis-construed by local governments, creating conflicts among some cities and counties. The Department of Housing and Community Development (HCD) has released guidance on these provisions, but some local agencies continue to reject this guidance. According to HCD, over 50 local governments have incorrectly applied state laws for ADUs and JADUs.
SB 543 cleans up existing state laws governing ADUs and JADUs to eliminate confusion and ensure they are properly applied at the local level.
SB 543 codifies multiple HCD permitting guidelines, including clarifying:
- HCD’s oversight and enforcement powers for JADU ordinances and permitting.
- Local governments have 15 business days to conduct an initial review of ADU permit applications, so homebuilders have time to fix errors in their application.
- Size, safety, and density standards for ADUs and JADUs.
- When local governments can charge impact fees for ADUs and JADUs.
Updates
- SB 543 was introduced on 2/20/25. It passed out of the Senate Housing Committee on 4/22/25. It passed the Senate Local Government Committee on 4/30/25. SB 543 passed the Senate floor on 5/27/25 by a vote of 39-0. It now heads to the Assembly for further action.
Authors
- Jerry McNerney (SD 5)
Sponsors
- Casita Coalition