ADU Rules: Oxnard vs Simi Valley
How do adu rules rules compare between Oxnard, CA and Simi Valley, CA?
Oxnard and Simi Valley have similar restriction levels.
Oxnard, CA
Ventura County
Oxnard permits ADUs in all residential and mixed-use zones following California ADU law. Detached ADUs may be up to 1,200 sq ft. Attached ADUs are limited to 50% of the primary dwelling or 1,200 sq ft, whichever is less.
View full Oxnard rules →Simi Valley, CA
Ventura County
Simi Valley permits accessory dwelling units consistent with California ADU laws (Government Code 65852.2). ADUs up to 1,200 square feet are allowed on single-family lots with streamlined permitting and reduced fees.
View full Simi Valley rules →Key Facts Comparison
| Fact | Oxnard | Simi Valley |
|---|---|---|
| Detached Max Size | 1,200 sq ft | - |
| Height Limit | 16 ft general, up to 25 ft near transit | - |
| JADU | Up to 500 sq ft within existing home | - |
| Parking | Not required near transit | - |
| Processing | Ministerial approval within 60 days | - |
| Max Size (Detached) | - | 1,200 square feet |
| Max Height | - | 16 feet (18 feet some cases) |
| Setbacks | - | 4 feet side and rear |
| Approval Timeline | - | 60 days by state law |
Highlighted rows indicate differences between cities.
Oxnard FAQ
Can I build an ADU in Oxnard?
Yes. ADUs are permitted in all residential and mixed-use zones. Detached units can be up to 1,200 sq ft with a 16-foot height limit. No additional parking is needed if you are within half a mile of transit.
Can I sell my ADU separately in Oxnard?
No. Under California law, ADUs generally cannot be sold separately from the primary residence, though they may be rented.
Simi Valley FAQ
Can I build an ADU in Simi Valley?
Yes, California law allows one ADU and one JADU on single-family lots. Detached ADUs up to 1,200 square feet are permitted with 4-foot setbacks from side and rear property lines.
Do I need to add parking for an ADU?
Garage conversions are exempt from replacement parking by state law. New detached ADUs may require one parking space unless within half a mile of transit or in other exempt categories.
How long does ADU permit approval take?
State law requires the city to approve or deny ADU applications within 60 days of a complete application. Contact Community Development at (805) 583-6800 for current processing times.
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