Adu Construction Bay Park, CA

Detached ADUs have a maximum allowed size of 1,200 square feet, regardless of the primary residence's size. A detached ADU must be at least six feet from any existing structures on the same lot to comply with fire safety codes. If the eave-to-eave distance between the ADU and another structure is less than 10 feet, fire-resistant materials and additional fire separation measures may be required.

If you own a vacant lot, you must first construct a primary home before applying for an ADU permit. However, under Senate Bill 9, certain single-family lots may be eligible for a lot split, allowing a new home on each lot, which could then qualify for an ADU.

ADUs in San Diego generally do not require any new parking. However, in the Beach Impact Area of the Coastal Overlay Zone, one parking space may be required for a new detached ADU unless the ADU is within half a mile of transit, under 500 square feet, part of the main home, or qualifies for another exemption.

San Diego's approach to building mandates compliance with the California Building Code to ensure the safety and welfare of future occupants. This includes but is not limited to structural integrity, fire safety, utilities, and access. ADU projects must meet specific seismic, fire-resistance, and egress standards.

Homeowners who build ADUs on their property can benefit from the additional rental income while contributing to the housing supply in San Diego. Rental rates vary by neighborhood and unit size. We can help you assess income potential for your specific San Diego location.

San Diego allows multifamily properties to convert existing spaces (garages, basements, storage rooms) into ADUs without numeric limits, provided they meet building codes for safety, ventilation, and energy efficiency. For single-family properties, conversion typically follows standard ADU rules.