What are the solar requirements for ADUs?

Newly constructed ADUs are subject to the Energy Code requirement to provide solar panels if the unit(s) is a newly constructed, non-manufactured, detached ADU. Per the California Energy Commission (CEC), the panels can be installed on the ADU or on the primary dwelling unit. ADUs that are constructed within existing space, or as an addition to existing homes, including detached additions where an existing detached building is converted from non-residential to residential space, are not subject to the Energy Code requirement to provide solar panels.

Please refer to the CEC on this matter. For more information, see the CEC’s website. You may email your questions to: title24@energy.ca.gov, or contact the Energy Standards Hotline at 800-772-3300. CEC memos can also be found on HCD’s website.

For important information for homeowners thinking of going solar, reference the California Public Utilities Commission (CPUC)'s California Solar Consumer Protection Guide.