Accessory Structures in Simi Valley, CA (2026)
5 verified accessory structures rules for Simi Valley, California, sourced directly from the municipal code and official government pages.
Verified from official government sources
ADU Rules
Simi Valley permits one ADU plus one JADU per single-family lot ministerially under SVMC 9-44.160, conforming the city to state law (Gov't Code 65852.2 and 65852.22) with 4-ft side/rear setbacks, 18-ft height, and up to 1,200 sq ft detached.
ADUs ministerial under SVMC 9-44.160
Few RestrictionsSimi Valley Municipal Code § 9-44.160(A) — Accessory Dwelling Units (Ministerial), General Provisions (Ord. No. 1316, adopted Nov. 2, 2020)
Notwithstanding any other regulation in this Development Code that is specifically applicable to ADUs or JADUs, a Zoning Clearance must be ministerially reviewed for an application for a building permit to create an ADU and/or a JADU within a residential zone subject to the development standards set forth in this section. The City reserves the right to limit construction of ADUs or JADUs in loc...
Shed Rules
Detached freestanding sheds and similar nonresidential accessory structures must sit at least 20 ft from the front, 3 ft from side and rear lot lines per SVMC 9-30.080 Table 3-2, may cover no more than 40% of any yard, and require a building permit if the floor area exceeds 120 square feet.
Sheds: 120 sq ft permit threshold, 3-ft setbacks
Some RestrictionsSimi Valley Municipal Code § 9-30.080, Table 3-2 — Setbacks for Architectural Features and Accessory Structures (Ord. No. 1316, Part 3)
TABLE 3-2 - SETBACKS FOR ARCHITECTURAL FEATURES AND ACCESSORY STRUCTURES ... Gazebos, carports, sheds, and similar nonresidential structures that are freestanding: Front 20 feet; Street Side / Side / Rear 3 feet. ... * Accessory structures shall not cover more than 40 percent of any yard except for Accessory Dwelling Units which are subject to yard coverages as outlined in Section 9-44.160.
Garage Conversions
Simi Valley ministerially allows an attached or detached garage to be converted to an ADU under SVMC 9-44.160(E)(1) — no additional setbacks are required when keeping the existing footprint, and lost garage parking is generally waived under state law.
Garage-to-ADU conversion allowed, no new setbacks
Few RestrictionsSimi Valley Municipal Code § 9-44.160(E)(1)–(2) and § 9-44.160(A)(17) — Detached ADU Requirements (Ord. No. 1316, Part 5)
Detached ADUs may be new construction in yards subject to setbacks outlined in Section B or the conversion of a legally permitted accessory structures, such as a studio, shed, carport, horse stable, garage, or pool house, can be converted to an ADU. The existing space of an accessory structure within which an ADU is proposed to be located must have a solid roof and structural framing. In additi...
Carport Rules
Simi Valley regulates carports as accessory structures under SVMC 9-30.080 (Table 3-2 setbacks; accessory structures may not cover more than 40 percent of any yard) and as covered parking under Chapter 9-34 (parking stall must be a clear 9 by 18 feet with no encroachment from posts). A building permit is required, and ADU-replacement carports must follow SVMC 9-44.160.
accessory-structures/carport-rules
Some RestrictionsTiny Homes
Tiny homes on foundations in Simi Valley are regulated as ADUs or standard dwellings and must meet California Building Code requirements. Tiny homes on wheels are classified as RVs and may not be used as permanent residences on residential lots.
Simi Valley Tiny Home Regulations
Some RestrictionsLooking for Ventura County county-wide rules?
County ordinances apply to unincorporated areas and may supplement Simi Valley city rules.
Accessory Structures in Ventura County →