AB 3074: The Law That Created Zone Zero

The fires that changed everything

In October 2017, the Diablo winds arrived early and with unusual force. On the evening of October 8th, more than a dozen wildfires ignited simultaneously across Northern California. The Tubbs Fire, which started near Calistoga around 9:45 PM, traveled 19 kilometers in its first three hours, crossing Highway 101 and reaching the Santa Rosa city limits before most residents were awake. By the time it was contained, it had burned 36,807 acres, destroyed 6,957 structures, and killed 22 people. At the time, it was the most destructive wildfire in California history.

That record lasted barely a year. On the morning of November 8, 2018, a transmission line owned by Pacific Gas & Electric failed in the Feather River Canyon during another bout of high winds. The Camp Fire raced through Butte County at a speed that gave residents of the town of Paradise almost no time to flee. Within hours, the fire had destroyed most of the town. When it was finally contained on November 25, 85 people were dead, many found in their cars on evacuation routes, and 18,793 structures had burned. The estimated economic damage was $16.5 billion. PG&E, facing wildfire liabilities estimated at $30 billion, filed for bankruptcy in January 2019.

Together, the 2017 and 2018 fire seasons killed more than 100 Californians, destroyed over 32,000 structures (more than 95% of them residences), and burned approximately three million acres. Insurance companies began pulling out of high-risk areas at scale. The state's existing defensible space framework, a two-zone system requiring vegetation clearance from 0 to 30 feet and 30 to 100 feet from structures, clearly wasn't enough. Scientists and fire professionals had known for years what the problem was. Now the public and the legislature were ready to listen.

The ember science

The most important thing fire scientists knew, and had documented extensively, was that most homes don't burn because flames reach them directly. They burn because of embers. Wind-driven embers can travel miles ahead of the main fire front, landing on and around structures before the fire itself arrives. According to CAL FIRE, up to 90% of home ignitions during wildfires are caused by embers, not direct flame contact.

The Insurance Institute for Business and Home Safety (IBHS) had been studying this mechanism for years. In controlled tests, they showered demonstration homes with simulated ember storms. A home surrounded by five feet of concrete pathways with no combustible material adjacent to the structure withstood the ember storm with no damage. An identical home with plants next to its walls and a wood fence attached to it was completely destroyed. The institute's research stated that embers and wind-blown burning ground debris were the most prevalent threat to homes, and that well over 90% of houses were ignited in the absence of direct flame or radiant heat.

California's existing defensible space requirements addressed the 30-to-100-foot zone reasonably well. But the first five feet, where embers accumulate, where wood mulch smolders against a wall, where a wood fence serves as a direct ignition pathway, was essentially unregulated. The Board of Forestry had discussed establishing standards for this zone as early as 2019, but there was no statute requiring it, and no timeline mandating action.

Drafting the bill

Assemblymember Laura Friedman, representing California's 43rd Assembly District (centered on Glendale and Burbank), had watched the 2017 and 2018 fire seasons with particular attention. Her district lay in the foothills above Los Angeles, in the heart of the urban-wildland interface. She had seen constituents lose homes, lose insurance, and lose confidence that the state was doing everything possible to protect them.

Friedman and her staff worked with CAL FIRE officials and fire scientists to identify the most impactful intervention that state law could mandate. The answer pointed consistently to the same place: the first five feet. In early 2020, Friedman introduced Assembly Bill 3074, titled “Fire prevention: wildfire risk: defensible space: ember-resistant zones.” The bill's goal was straightforward: establish in statute that a five-foot ember-resistant zone was required around all structures in Fire Hazard Severity Zones, and direct the State Board of Forestry and Fire Protection to develop the specific regulations to implement it.

The bill required the Board to update its defensible space regulations by January 1, 2023. Implementation would be phased: the new zone would take effect immediately for new construction once regulations were finalized, and one year later for existing structures. The legislature also built in explicit language stating its intent that enforcement be phased in over time and that CAL FIRE pursue collaborative approaches, not punitive ones, as the default.

Passage and support

AB 3074 moved through the legislature with striking speed and breadth of support. In a deeply polarized political environment, the bill passed with unanimous bipartisan votes in both chambers. The coalition supporting it included 30 organizations: environmental groups, fire safety nonprofits, insurance industry representatives, and local government associations. The Insurance Institute for Business and Home Safety threw its weight behind the bill. Sierra Club California was among the supporters. So were CAL FIRE and the California Fire Chiefs Association.

The California Association of Realtors and some local government associations raised concerns about implementation costs and enforcement burden. These were addressed in part by provisions requiring notice to property owners before penalties were imposed, and by making the Board's rulemaking contingent on legislative appropriation, ensuring the Board had resources before enforcement began.

Governor Gavin Newsom signed AB 3074 on September 29, 2020. It was chaptered as Chapter 259, Statutes of 2020, and took effect January 1, 2021. California had created Zone Zero in law. The harder work of turning that statutory mandate into enforceable regulation was just beginning.

What AB 3074 actually does

AB 3074 amended three sections of California law: Sections 51182 and 51186 of the Government Code, and Section 4291 of the Public Resources Code. In practical terms:

Created the Zone Zero mandate in statute. For the first time, California law explicitly required an ember-resistant zone within five feet of all structures in High and Very High Fire Hazard Severity Zones, covering both the State Responsibility Area and designated zones in Local Responsibility Areas.

Directed the Board of Forestry to write the regulations. The bill did not itself specify what was and wasn't allowed in Zone Zero. That task was delegated to the Board of Forestry and Fire Protection, in consultation with the Office of the State Fire Marshal, to consider eliminating materials that would likely be ignited by embers.

Established a phased implementation timeline. Zone Zero requirements would take effect for new structures immediately upon the Board finalizing regulations. For existing structures, requirements would take effect one year later, extended to three years by SB 504 in 2024.

Required local notification before enforcement. Local agencies were required to notify residents about the requirements before imposing penalties. CAL FIRE was prohibited from changing its inspection practices until the State Fire Marshal certified that sufficient resources had been appropriated.

Set cost-contingent rulemaking. The Board's obligation to promulgate regulations was contingent on a legislative appropriation, a practical protection against unfunded mandates that also contributed to years of delay in getting the rulemaking started.

Five years of delays

AB 3074 became law in January 2021. The Board of Forestry did not finalize Zone Zero regulations in 2023. Nor in 2024. Despite the statute's urgency and the fire science's clarity, the rulemaking process moved slowly through successive rounds of public workshops, committee deliberations, and draft revisions.

The core scientific question of whether removing combustible material from the immediate perimeter of a home reduces ignition risk was never seriously disputed among fire professionals. The delays came from a different direction: the question of what, specifically, homeowners would be required to do. Particularly in Southern California, where urban neighborhoods blend into fire-prone hillsides, mandatory vegetation removal generated intense pushback. Homeowners raised concerns about shade, aesthetics, water runoff, and habitat. Landscaping interests argued that well-maintained vegetation could serve as a fire buffer. Local officials worried about the enforcement burden.

SB 504, passed in 2024, extended the existing-structure implementation timeline from one year to three years and added grant program reforms to help communities fund compliance. But it did not end the delay. By fall 2025, with a Zone Zero Advisory Committee holding public workshops, near-final language was on the table. Then, in late 2025, the December 31 deadline passed without adoption.

The LA fires change everything again

In January 2025, the Palisades and Eaton fires burned through Los Angeles County with a ferocity that shocked even veteran fire professionals. The fires destroyed approximately 16,000 structures. Media coverage drew immediate attention to the fact that Zone Zero regulations, designed specifically to address ember-driven ignition in exactly this kind of urban-wildland interface fire, were still not in effect five years after AB 3074 had passed.

On February 6, 2025, Governor Newsom issued Executive Order N-18-25, directing the Board of Forestry to complete and adopt final Zone Zero regulations by December 31, 2025. Representative Friedman, now serving in Congress, celebrated the order: “It's past time we get these commonsense rules written and shared with the public. Not only will they help protect homes from wildfires, but they will help lower costs for homeowners and renters by lowering insurance rates.”

AB 1455, introduced in 2025, authorized the Board to adopt Zone Zero regulations on an emergency basis, bypassing the normal administrative rulemaking timeline. Even with the executive order and emergency authorization, the December 31, 2025 deadline passed without final regulations. The Zone Zero Advisory Committee resumed work in early 2026, and the Board released an updated draft in April 2026 prioritizing education and outreach over penalties during the initial implementation period.

Where things stand today

As of June 2026, Zone Zero is law. It has been since January 2021. But final regulations have not yet been adopted. The Board of Forestry's April 2026 draft represents the most current published version of what compliance will look like.

When regulations are finalized, new construction must comply immediately. Existing structures will have approximately three years to achieve Phase 1 compliance and up to five years for Phase 2 requirements set by local AHJs. One immediate restriction, no new combustible fences within Zone Zero, is expected to take effect upon adoption regardless of phase timeline.

Enforcement will follow an education-first model. The April 2026 draft confirms that the initial compliance period will prioritize outreach and voluntary compliance over citations. The rulemaking Friedman initiated in 2020 is not finished, but California is closer than it has ever been to having enforceable standards for the first five feet.

References & sources

• AB 3074 Full Bill Text, California Legislative Information
• AB 3074 Status and History, LegiScan
• Defensible Space Zones 0, 1 & 2, Board of Forestry
• Zone 0: When the Deadline Passed, Oakland Firesafe Council
• Zone Zero Mandates Near Completion, Sierra Club
• Understanding California's Zone 0 Regulations, MySafe:LA
• After Devastating LA Fires, California Drafts Nation's Toughest Rules, NPR
• Friedman Statement on Executive Order N-18-25, Rep. Laura Friedman
• AB 3074 and Zone Zero Compliance Guide, Ember Pro
• Board of Forestry April 2026 Draft, Coastside Buzz
• Camp Fire (2018), Wikipedia
• Zone Zero Sparks Debate Among LA Residents, ABC7