California ADU is a project by UC Berkeley’s Center for Community Innovation. The project was first established in 2019 to research ADU ordinances across the state to identify best practices for facilitating the uptake of California’s ADU enabling legislation. The first phase of this work was conducted from 2019-2021 and the second phase, with similar goals, but different methodology began in 2023.
This website features list of best practices, a list of the project’s ADU publications, and an interactive map-based visualization for exploring ADU permitting and production across the California. It also shares the findings of the first phase of the project in the previous research section.
Best practices from jurisdictions across the state including financing, pre-approved units, public information, and policies
Interactive map-based visualization of California ADU permitting and production from 2018-2022
Select publications from the Center for Community Innovation’s ADU research
Findings and jurisdiction grades from the 2019-2021 ADU research project