Simi Valley, CA Building Setbacks & Zoning: Setback Rules (2026)

Required minimum setbacks for unincorporated Ventura County are set out in the development standards tables of the Non-Coastal Zoning Ordinance: Section 8106-1.1 for Open Space, Agricultural Exclusive, and Residential zones, and Section 8106-1.2 for Commercial, Industrial, and Special Purpose zones. In the OS-REC, OS, AE, RA, RE, RO, R1, and R2 residential and rural zones, the required front setback is 20 feet, the interior side and corner setback is 5 feet (10 feet on the street side of a reverse corner lot), and the rear setback is 20 feet (15 feet for reverse corner street-side situations per the table). RHD and RPD zones use different standards (front setbacks measured 10 feet from adjacent street, 5-foot interior side, 10-foot rear for RHD; RPD setbacks are as specified by permit). In commercial and industrial zones, CO requires a 20-foot front and 5-foot side setback (10 feet adjacent to a side yard situation per the table); industrial M1/M2/M3 setbacks range from 10 to 20 feet from the street with a 5-foot setback if adjacent to an R-zone, and a 30-foot setback applies where an industrial use is adjacent to or across from any R-zone. Structural retaining walls are exempt from these setbacks (Section 8106-8.1.7). Exceptions to required setbacks are found in Sections 8106-5, 8106-6, 8107-1.7, and 8107-20, and flag/irregular lots use Section 8106-4.3. Because setbacks differ by zone and lot configuration, confirm your parcel's zone with the Planning Division before building.