Zone Zero Regulations in Topanga | AB 3074, SB 504 & the Zone 0 Rule
The Law · Explained Plainly

Zone Zero Regulations for Topanga Homeowners

Three state laws create the ember-resistant zone: AB 3074 (2020) defines the 0-5 ft zone, SB 504 (2024) and AB 1455 (2025) set the rulemaking path. The Board of Forestry's April 17, 2026 draft is the current text, and in Topanga the LA County Fire Department is the authority that applies it.
The statutes

The three laws behind Zone 0

California's defensible-space law has covered 30 and 100 foot zones for decades, and every Topanga homeowner who has hosted a county inspector knows it. Zone 0 adds a third, innermost band, and it is the strictest of the three.

LawYearWhat it does
AB 30742020Creates the ember-resistant zone: the first 5 feet around structures in Very High Fire Hazard Severity Zones must be kept free of combustible material.
SB 5042024Directs the Board of Forestry to finish the Zone 0 regulations and clarifies how the rules reach existing homes, not just new ones.
AB 14552025Refines the rulemaking timeline and enforcement framework, including the phased approach for existing structures.
April 17, 2026 draft2026The Board of Forestry's current working text: phased deadlines, immediate rules for new fences and rebuilds, and education-first enforcement. Final adoption expected late 2026.
The state sets the floor. The county writes the specifics.

Because Topanga is unincorporated, LA County Fire is your Authority Having Jurisdiction. County decisions control Phase 2 timing, inspection practice, and how the tree and vegetation language is read on canyon parcels. When state and county guidance differ, the county's implementation is the one that shows up at your gate.


What it covers

What counts as combustible in the first five feet

The ember-resistant zone regulates everything that can catch an ember within 5 feet of a structure, not just plants:

  • Combustible mulch and bark against the foundation.
  • Dead or dying vegetation, and per the draft most live combustible plants in the band.
  • Wood fences and gates where they attach to or run within 5 feet of the house. This is the one canyon homeowners most often miss.
  • Firewood, lumber, and stored combustibles, including under decks.
  • Combustible outdoor furniture and trellises in the band.

What stays: hardscape, gravel, stone, pavers, well-irrigated low plantings where the final rules allow them, and mature trees whose canopies are maintained, subject to the final text and county guidance.

Common Questions

Zone 0 law questions from the canyon

Is Zone 0 law in Topanga right now?

The statutes are law, but the enforceable regulations are still in draft. The Board of Forestry's April 17, 2026 draft is the most current text, and final regulations are expected late 2026. Once adopted, new-fence and rebuild rules apply immediately and existing homes get phased deadlines.

Who writes the rules that actually apply to my Topanga parcel?

The state sets the floor, and the Los Angeles County Fire Department, Topanga's Authority Having Jurisdiction, applies and enforces it locally. County-level choices decide Phase 2 timing and how inspections run in the canyon.

Does Zone 0 apply to decks, fences, and sheds, or just plants?

It covers combustible material of every kind in the first 5 feet: mulch, vegetation, wood fencing attached to the structure, stored firewood, and combustible items. That is what makes it broader than the brush clearance Topanga already knows.

My home is on a shared driveway off Fernwood. Does Zone 0 cover accessory structures?

The draft applies the ember-resistant zone to structures generally, and detached buildings like studios and sheds common on Topanga parcels can carry their own 5-foot zone. A licensed contractor or LA County Fire can confirm how the final text treats your outbuildings.

Translate the statutes into a to-do list

A free assessment walks your actual parcel and maps each requirement to what you own. Clear, written, no obligation.