Can you build an ADU in San Jose, CA?
The city has an active ADU program, public checklist, preapproved plans, and explicit allowance for ADUs on residentially zoned properties. Site-specific constraints such as lot conditions, flood hazard, and building code issues still need review.
Confidence: high · Last researched May 2026
ADU rules
ADUs are small living units with a kitchen and bathroom and are allowed on residentially zoned properties, including single-family, duplex, and multifamily properties, subject to city rules and permit review.
- Residential zoning required.
- Use the city ADU Universal Checklist to determine eligibility.
- The city offers preapproved ADU plans.
- State ADU legislation is implemented through the city zoning code and reflected in the checklist.
Dimensional standards in San Jose, CA
| R-1-8 — front setback | 25 feet — Cited in a secondary site-plan guide; verify in adopted code. |
| R-1-8 — side setback | 5 feet minimum (10% of lot width, 5 ft min) — Cited in a secondary site-plan guide; verify in adopted code. |
| R-1-8 — rear setback | 20 feet — Cited in a secondary site-plan guide; verify in adopted code. |
| R-1-5 — front setback | 20 feet — Cited in a secondary site-plan guide; verify in adopted code. |
| R-1-5 — side setback | 5 feet — Cited in a secondary site-plan guide; verify in adopted code. |
| R-1-5 — rear setback | 20 feet — Cited in a secondary site-plan guide; verify in adopted code. |
| R-2 — front setback | 20 feet — Cited in a secondary site-plan guide; another secondary source cited "15 feet." Verify in adopted code. |
| R-2 — side setback | 5 feet — Secondary source only; verify in adopted code. |
| R-2 — rear setback | 20 feet — Cited in a secondary site-plan guide; another secondary source cited "15 feet." Verify in adopted code. |
| R-M — front setback | 20 feet — Secondary source only; verify in adopted code. |
| R-M — side setback | 10 feet (or height-dependent) — Secondary source only; verify in adopted code. |
| R-M — rear setback | 20 feet — Secondary source only; verify in adopted code. |
| Detached ADU — rear and side setback | 4-foot setbacks — Cited in secondary source and generally consistent with California ADU frameworks, but verify against city ADU checklist and ordinance. |
Related questions
Are ADUs allowed in San Jose, CA?
ADUs are small living units with a kitchen and bathroom and are allowed on residentially zoned properties, including single-family, duplex, and multifamily properties, subject to city rules and permit review.
Full investor analysis
You've seen the general rule. The full San Jose, 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 Jose, CA report free →More about San Jose, 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 Jose, CA officials before making decisions.
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