Before You Build in Simi Valley, CA: Permit & Rule Checklist (2026)

Simi Valley enforces California Building Code pool barrier requirements mandating fences or walls at least 5 feet tall with self-closing, self-latching gates around all residential swimming pools, spas, and hot tubs.

Simi Valley requires building permits for retaining walls over 4 feet in height and engineering for walls supporting surcharges. Retaining walls are common in the city's hillside areas and must meet structural and drainage standards.

Simi Valley Municipal Code Section 9-30.050 limits residential fences to roughly 42 inches in the front yard and 6 feet in side and rear yards, measured from the highest adjacent grade. Walls/fences up to 8 feet are allowed along arterial streets or where a property abuts a commercial/industrial zone.

Simi Valley requires a Zoning Clearance from the Planning Division before installing, altering, or replacing a property line wall or fence. A Building Permit is generally not required for standard residential fences at or under 6 feet, but is required for garden walls over 6 feet, retaining walls, and any fence over 24 inches in a Traffic Safety Sight Area.

California's Good Neighbor Fence Act (Civil Code 841) applies in Simi Valley, requiring adjacent property owners to share equally in the cost of maintaining boundary fences. The city does not mediate private fence disputes but enforces code compliance.

Hot tubs and spas in Simi Valley are subject to the same barrier, permit, and safety requirements as swimming pools. Portable hot tubs with locking covers may satisfy barrier requirements but still need electrical permits for hard-wired installations.

Above-ground pools in Simi Valley must meet the same safety requirements as in-ground pools. Pools with walls at least 60 inches may use walls as part of the barrier system.

When a Simi Valley building permit is issued for a new or remodeled pool or spa, California's Swimming Pool Safety Act requires at least two of seven drowning-prevention safety features, typically including a code-compliant enclosure isolating the pool from the house.

A new pool or spa in Simi Valley requires a Zoning Clearance from the Planning Division to confirm setbacks, followed by a building permit from the Building & Safety Division; both are issued at City Hall, 2929 Tapo Canyon Road.

Simi Valley swimming pool owners must maintain pools in a safe and sanitary condition, including proper chemical treatment, functioning equipment, and anti-entrapment drain covers. Unmaintained pools creating mosquito breeding conditions are subject to abatement.

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.

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.

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 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.

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.

Open burning of yard waste, trash, and debris is prohibited in Simi Valley. The Ventura County Air Pollution Control District and Ventura County Fire Protection District enforce strict no-burn policies with limited agricultural exceptions.

Simi Valley allows recreational fire pits and outdoor fireplaces on residential properties subject to Ventura County Fire Protection District regulations. Fire pits must maintain specific clearances from structures and combustible materials.

Simi Valley has a tree preservation ordinance that protects native oaks and significant trees from unauthorized removal. Permits are required to remove protected trees, and replacement planting or in-lieu fees are typically required.

Under Simi Valley Municipal Code Chapter 9-38 (Mature Tree Preservation Ordinance), all mature native oak trees and all historic trees are protected citywide, and all other mature trees are protected except in single-family-home yards. Routine pruning that does not endanger the tree's life is permitted, but removing or heavily pruning a protected tree requires a Tree Removal Permit from the Environmental Services Director.

Simi Valley's Ventura County Waterworks District No. 8 imposes year-round permanent water conservation standards under Ordinance WWD-08 (2009), including watering only before 9:00 a.m. or after 5:00 p.m., a 15-minute-per-zone irrigation cap, and prohibitions on washing hardscapes and non-recirculating fountains. The Board of Directors can declare Stage I through Stage IV water supply shortage conditions that layer additional restrictions on top of the permanent rules.