Ventura's Accessory Structures: The Rules That Matter

Every city handles accessory structures a little differently. In Ventura, California, there are 5 distinct rules that residents and property owners should be aware of. Some are stricter than what neighboring cities enforce, and others are more relaxed. Here is what you need to know.

Tiny Homes

Tiny homes on permanent foundations in Ventura are treated as ADUs or JADUs under SBMC Chapter 24.430 and must meet minimum size requirements (150 sq ft). Tiny homes on wheels are generally classified as recreational vehicles and cannot be used as permanent dwellings in residential zones.

Key details: On Foundation: Treated as ADU — 150 sq ft minimum. On Wheels: Classified as RV — not a permanent dwelling. Building Code: Full CA Building Code compliance required. ADU Pathway: SBMC Chapter 24.430. RV Parking: SBMC 16.217 restrictions apply to THOWs.

Living in a tiny home on wheels in a residential zone may result in code enforcement action. Unpermitted foundation-based tiny homes require retroactive permitting or removal.

Carport Rules

Carports in Ventura require building permits and must comply with zoning setback and lot coverage requirements. Carports count toward the maximum lot coverage in residential zones. Design must be compatible with the residential character of the neighborhood.

Key details: Permit: Building permit required. Lot Coverage: Counts toward zone maximum. Setbacks: Must meet zoning district requirements. Design: Compatible with neighborhood character. Contact: Community Development (805) 654-7869.

Unpermitted carports face code enforcement action, stop-work orders, and potential removal. Non-compliant structures may require retroactive permitting with penalty fees.

ADU Rules

Ventura regulates ADUs under SBMC Chapter 24.430. ADUs cannot be smaller than 150 sq ft. Attached ADUs may be up to 800 sq ft or 50% of the primary residence (whichever is greater). Detached ADUs must provide 6-foot separation from the primary dwelling. Colors and materials must match the primary unit.

Key details: Minimum Size: 150 sq ft. Max Attached: 800 sq ft or 50% of primary (greater of). Height: 25 feet or primary dwelling height (greater). Separation: 6 feet from primary for detached ADUs. Solar: Required on new detached ADUs (Energy Code).

Unpermitted ADUs face stop-work orders, mandatory permitting with penalty fees, and possible removal. Non-compliant ADUs may not be occupied until brought into compliance.

Shed Rules

Accessory structures in Ventura require building permits for those over 120 sq ft. Must meet setback requirements per SBMC Title 24. In Very High FHSZ areas, non-combustible or fire-resistant materials are strongly recommended.

Key details: Permit Threshold: Over 120 sq ft. Setbacks: Per SBMC Title 24 zoning. FHSZ Areas: Fire-resistant materials recommended. Topic: Shed Rules.

Shed over 120 sq ft without permit: double retroactive fees. Shed in setback area: code enforcement notice, 30 days to relocate or remove, $100-$500/day. Shed used as living space: serious zoning violation with immediate enforcement.

Garage Conversions

Garage conversions to ADUs are allowed per CA state law. Existing setbacks are exempt. Replacement parking is not required when a garage is converted to an ADU. Thomas Fire rebuild area conversions followed expedited process (expired Dec. 31, 2025).

Key details: Conversion Allowed: Yes (ADU use). Setback Exemption: Existing setbacks apply. Replacement Parking: Not required. Thomas Fire: Expedited process expired Dec. 31, 2025.

Converting without permits: stop-work order, double retroactive fees, $100-$500/day. Occupying unpermitted conversion: zoning violation. Non-owner-occupied JADU: violation of JADU requirements.

The Bottom Line

Ventura's accessory structures rules are a mixed bag. Some areas are strict, others are relaxed, and the details matter. The best approach is to check the specific rule that applies to your situation rather than assuming Ventura is broadly strict or permissive.

These rules come from Ventura's publicly available municipal code. For complete penalty schedules, exemption details, and answers to common questions, see the individual ordinance pages throughout this guide.