ADU Regulations and Eligibility across San Diego County
California ADU law now lives in Government Code sections 66310 through 66342. Cities and the county apply local rules on top of that floor. Whether your garage qualifies for a full ADU or a JADU depends on attached versus detached, the proposed living facilities, and the department that reviews the address.
What to know
- California ADU law generally requires ministerial (staff-level, non-discretionary) approval for a code-compliant ADU on a residential lot
- Setback, height, and lot-coverage rules exist at both the state-law floor and the local jurisdiction level, and the more permissive of the two generally applies where state law preempts
- JADUs are capped at 500 square feet under state law and generally require an existing or proposed single-family home on the lot
- Owner-occupancy is not a statewide ADU rule. For a JADU, occupancy can be required when the unit shares sanitation with the house. Confirm the current rule for the address.
- Replacement parking for a garage converted to an ADU is barred by Gov. Code 66314(d)(11), with City of San Diego Beach Impact and some city exceptions to confirm at the counter
Common questions
Does every garage in San Diego County qualify for an ADU conversion?
Most residential garages qualify under California ADU law, but lot size, existing structures, and local zoning overlays can affect eligibility. The reviewing department and the licensed pro you hire confirm eligibility for the address.
Do I need to live in the main house to have an ADU?
California does not let cities impose an owner-occupancy requirement on a standard ADU. For a JADU, occupancy can apply when the unit shares sanitation facilities with the house, and not when it has its own. Confirm the current rule with the department that reviews the address.
Can an HOA block an ADU conversion?
California ADU law limits HOAs' ability to fully prohibit ADUs, but HOAs can still regulate reasonable design elements like exterior finish and color in some cases. Review your HOA's current governing documents alongside state law.
Where do I find the exact rules for my property?
Your city building department, or San Diego County Planning and Development Services for unincorporated areas, publishes current local ADU standards. State law sets the floor; local rules fill in the specifics for your address.
Have permit questions for your project?
We coordinate drawings, submittal, and inspections with insured local crews.