Can you build an ADU in San Diego, CA?
The city bulletin says ADUs are generally allowed in zones that permit residential uses and are allowable limited uses, although coastal sites may face different effective rules and project-specific constraints.
Confidence: high · Last researched May 2026
ADU rules
ADUs are attached or detached residential dwelling units allowed as limited uses in zones where the use regulation tables allow them, generally where residential uses are permitted.
- Must be 1,200 square feet in size or less
- Must provide complete independent living facilities
- Must be located on a lot with a proposed or existing single-dwelling unit or multiple-dwelling units
- Multiple ADUs, including Bonus ADUs, must comply with base zone rules on structure height, lot coverage, and maximum floor area ratio
- Some ADU rules differ in the Coastal Overlay Zone depending on Coastal Commission certification status
Related questions
Are ADUs allowed in San Diego, CA?
ADUs are attached or detached residential dwelling units allowed as limited uses in zones where the use regulation tables allow them, generally where residential uses are permitted.
Full investor analysis
You've seen the general rule. The full San Diego, CA report shows which districts allow ADUs by-right vs. by special permit, the approval path and timeline, and the overlay/flood constraints that quietly kill ADU projects here. First town report is free.
Get the full San Diego, CA report free →More about San Diego, CA zoning
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This summary is AI-generated from public municipal sources and is not legal, engineering, or land-use advice. Always verify zoning with San Diego, CA officials before making decisions.
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