San Diego requires a building permit for every new ADU or JADU and for work that creates or converts space into one.
This answers the permit requirement, not parcel approval. Zoning, coastal, fire, utility, historic, building-code, and site constraints still control the design.
What this tells youComputed rule answer
How precise this isComputed rule answer
Official data checkedSan Diego ADU/JADU Information Bulletin 400
Next stepCheck parcel rules and project scope before design, purchase, or contractor conversations.
ADU/JADU permitBuilding permit required
Applies toNew construction, addition, or conversion creating an ADU or JADU
Still verifyParcel zoning, coastal/fire/historic conditions, utilities, design, and building code