Fresno allows ADUs on residential lots that already have or will have a primary home, and runs a pre-approved plan program. Applications go straight to a building permit; a Zone Clearance is no longer required.[1]
What is an ADU? An accessory dwelling unit is a small second home on the same lot as the main house: a backyard unit, garage conversion, attached addition or guest house with its own kitchen and bath.
California cities can set their own ADU rules, but never stricter than state law. Grey lines show the state floor from the HCD ADU Handbook.
| Size limits | New detached ADU: up to 1,200 sq ft. New attached ADU: up to 50% of the existing home or 1,200 sq ft, whichever is less. Conversions of an existing detached structure or part of the main home can use the full existing structure.[2] State law: a city's maximum size must allow at least 850 sq ft, or 1,000 sq ft for more than one bedroom, and local rules cannot block an 800 sq ft ADU with 4 ft side and rear setbacks (Gov. Code 66321).[4] |
|---|---|
| Height | No city-specific figure verified. The state minimum below applies; confirm local details with the city. State law: detached ADUs get at least 16 ft; 18 ft within a half mile walk of a major transit stop or high-quality transit corridor (plus 2 ft to match roof pitch) or on a lot with a multistory multifamily building; attached ADUs up to 25 ft or the main home's limit if lower (Gov. Code 66321).[4] |
| Setbacks | 4 ft side and rear for new ADUs. Front setbacks follow the zoning district.[2] State law: side and rear setbacks can be no more than 4 ft for new ADUs; converted existing space needs no new setback (Gov. Code 66314, 66323).[4] |
| Parking | No off-street parking required for ADUs, per the city guidebook.[2] State law: at most 1 space per ADU or per bedroom, whichever is less, and none within a half mile walk of public transit, in a historic district, within one block of a car share, or for ADUs inside the house (Gov. Code 66314, 66322).[4] |
| Owner occupancy | No city-specific figure verified. The state minimum below applies; confirm local details with the city. State law: no owner occupancy requirement for ADUs (Gov. Code 66315). A JADU requires the owner to live on site if it shares a bathroom with the main home (Gov. Code 66333).[4] |
| Permit steps and timeline | Pre-approved and custom ADU plans submit directly for a building permit (no Zone Clearance). The city offers five pre-approved plans from 340 to 1,015 sq ft, with Craftsman, Contemporary and Gable elevations.[1] State law: the city must approve or deny a complete application within 60 days when there is an existing home on the lot (Gov. Code 66317).[4] |
| Fees | No city-specific figure verified. The state minimum below applies; confirm local details with the city. State law: no impact fees on ADUs of 750 sq ft or less; above that, impact fees must be proportional to the size of the main home. Plan check, permit and school fees can still apply.[4] |
Also worth knowing: Fire sprinklers may be required when the primary home has them, or when the ADU is too close to a property line or neighbor. Contact the ADU Hotline at adu@fresno.gov or (559) 621-8077.[1]
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Sources
Every fact above links to an official city or state page. Rules change; check the source before you build.
- [1] City of Fresno: ADU Program checked Oct 2026
- [2] City of Fresno: ADU and Small Home Guidebook (Mar 2023) checked Oct 2026
- [3] Fresno Municipal Code 15-2754 (Second/Accessory Dwelling Units) checked Oct 2026
- [4] HCD ADU Handbook (March 2026) checked Oct 2026