California fire rules for homes: who enforces what
What's law, what's coming, and what your insurer wants. Sorted out.
Zone 0 is the talk of California right now.
Neighbors trade notes. Contractors bring it up. Insurance letters mention it. And everyone has heard a different version.
Some of it is law. Some is coming. Some is just your insurer's list. One can fine you today, one could become law, and one decides whether you keep your coverage.
This article sorts out which is which, and what to do first.
Where things stand today
Zone 0 is the first 5 feet around a house, and it is partly law already.
California's defensible space law has two zones: Zone 1, the first 30 feet around a building, and Zone 2, from 30 to 100 feet [1]. Where that law applies, Zone 1 already sets some rules for the first 5 feet.
The new Zone 0 rule is not in force yet. And your insurer may already ask for more than either.
So a California home can face four checklists: the fire inspector's, the building inspector's, a voluntary insurance-industry standard called IBHS Wildfire Prepared Home, and your insurer's. Only the fire inspector can fine you today. The one most people need to pass is their insurer's.
Start with your address. It decides which law covers you. Check my address.
Which rules apply to my home?
- Pick where your home is. Not sure? Pick "Not sure".
- Answer the two yes or no questions.
- Read the list below. Start with the first step.
Your checklists
Answer the three questions to see which checklists apply and what to do first.
Who checks what
Look at the last column. Only the fire inspector can fine you over an existing home.
| Who | What they check | Who it applies to | Can they fine you? |
|---|---|---|---|
| Fire inspector | Defensible space out to 100 feet. Not Zone 0. Not the house itself. | Existing homes in State Responsibility Areas at any rating, homes in local Very High areas, and places with their own local codes [1][2]. | Yes. $100 to $500 for a first violation [3]. |
| Building inspector | The building code for fire zones, called the Wildland-Urban Interface (WUI) Code: ember-resistant roofs, vents, siding, doors and garage door gaps [4]. | New homes, additions and replaced parts in fire hazard zones. Not existing homes. | Not over an existing home. They check new work only. |
| IBHS evaluator | IBHS (the Insurance Institute for Business & Home Safety) runs Wildfire Prepared Home, a voluntary designation many insurers look at. Its evaluator checks the house and the first 30 feet [5]. | Only owners who apply. Voluntary. | No. They document. They don't advise or fine. |
| Insurer | Your home's risk, often from aerial images and risk models, plus their own requirements. | Anyone who wants a policy or a discount. | No. But they can turn you down, or not renew with 75 days' notice and the reasons [6]. |
| Consultant | Whatever they offer. Often a mix of IBHS items, building code and best practice. | Owners who hire one. | No. A consultant's report is advice, not the law. |
Here is the same thing around a house. Tap the house or a ring to see who asks for it.
The house
- IBHS Wildfire Prepared Home Class A roof, noncombustible gutters, ember-resistant vents or 1/8 inch mesh, and the bottom 6 inches of walls noncombustible.
- Building code, new work only Ember-resistant roofs, vents, siding, doors and garage door gaps. Only for new homes, additions and replaced parts.
The fire inspector checks the ground around it, not the house itself.
The first 5 feet (Zone 0)
- Law now Zone 1 starts at the wall, so some of it is law here: firewood out unless covered, nothing burnable under decks.
- New Zone 0 rule, not in force If it comes back as adopted: nothing burnable within 3 years for existing homes, like mulch, wood chips, firewood or dead leaves. Plant-free strips by walls, windows, vents and decks within 5 years.
- IBHS Wildfire Prepared Home Bare ground, no exceptions. No mulch, no plants.
5 to 30 feet (rest of Zone 1)
- Law now Dead plants cleared. Firewood out unless fully covered.
- IBHS Wildfire Prepared Home Defensible space out to 30 feet.
30 to 100 feet (Zone 2)
- Law now Defensible space out to 100 feet, or to your property line if closer.
Only the defensible space law reaches this far.
Law now means the defensible space law: Zone 1, the first 30 feet, and Zone 2, 30 to 100 feet. It applies in State Responsibility Areas at any rating and in local areas rated Very High. Only it can fine you over an existing home.
Four questions, short answers
Is Zone 0 required by law?
Not yet. The goal of Zone 0 is nothing in the first 5 feet that embers can light.
State law already says the 100 feet must include "an ember-resistant zone within 5 feet." But it only starts for new buildings once the Board of Forestry updates its regulations, and for existing buildings 3 years after that [1].
The Board adopted its Zone 0 rule on August 19, 2026, then withdrew it from state review on September 8 [8]. As of October 18 it has not been refiled.
Where the 100-foot law applies, some items near the house are already law: a clean roof, no tree within 10 feet of a chimney, no dead wood over the house, firewood out of the first 30 feet unless covered, nothing burnable under decks [1][9].
Do California's defensible space requirements apply to me?
State Responsibility Area, any rating: yes, including Moderate. Since January 1, 2025 it covers any building in one, not only land with brush or forest [1][10].
Local area rated Very High: yes, for occupied buildings [2].
Local area rated High, Moderate or none: no statewide duty. Your city or county may have its own.
Check your address to see which area you are in.
Who checks?
CAL FIRE, or a county or fire district working with it. In Sonoma County, for example, the county is the inspection authority under an agreement with CAL FIRE [11].
Statewide, CAL FIRE and partner counties did over 200,000 inspections a year around 2020. In 2019-20, 86% passed [12].
What can they do?
Fines: $100 to $500 for a first violation, $250 to $500 for a second within 5 years, and a misdemeanor of $500 or more for a third. The agency can also do the work and bill you [3].
In Sonoma County, for example, you get 30 days to fix it. After that come hearings, fees and county clearing at your cost [13].
Citations are rare. Fewer than 1,000 in 2019-20, or about 1 in 200 inspections [12].
Selling? In a State Responsibility Area rated High or Very High, or a local Very High area, the seller gives proof of a defensible space inspection from the last 6 months, or the buyer agrees in writing to comply within a year [14].
Who really asks for these?
Each item below often gets blamed on the wrong checklist. The tags say who actually asks for it.
Garage door gaps of 1/8 inch
Building code
The WUI Code caps garage door gaps at 1/8 inch, with weatherstripping, overlaps or metal flashing [4].
That covers new or replaced doors in fire hazard zones. It is not law for your existing door.
6 inches of noncombustible wall at the base
IBHSInsurance discount
Wildfire Prepared Home requires the bottom 6 inches of outside walls to be noncombustible [5]. It is also on the state's list of actions insurers must give a discount for [15][16].
Not law for existing homes. A similar 6-inch rule is proposed for the building code, for new work only, and is not in effect [17].
1/8 inch mesh on vents
IBHSBuilding code (new work)
Wildfire Prepared Home has two levels. The first, Essential, wants ember-resistant vents or 1/8 inch mesh, and mesh under decks 4 feet high or lower. The higher level, Enhanced, adds soffit vents (under the eaves), skylights that open and the space under open stairs. No mesh on dryer vents [5].
The WUI Code also covers vents, for new work only [4].
Wood siding
IBHSBuilding code (new work)
Wildfire Prepared Home's higher level, Enhanced, allows no wood siding at all, even treated [5]. Essential allows it, with the bottom 6 inches noncombustible.
The WUI Code covers siding on new work [4].
Mulch in the first 5 feet
IBHSZone 0 rule, not in force
Not state law yet. IBHS requires it gone: no mulch, no plants [7][18]. The new Zone 0 rule would require it too, within 3 years for existing homes [19].
What changes if Zone 0 takes effect
Not in force. The Board would have to refile the rule and the state would have to sign off. Even then, CAL FIRE can't change its inspections for it until the State Fire Marshal finds in writing that the Legislature paid for it [1].
Here is what the Board adopted on August 19, 2026, if it comes back as is [19]. It covers every building in a State Responsibility Area at any rating, and occupied buildings in local Very High areas.
- New buildings: day one.All of Zone 0 from the start.
- Existing homes, right away.Roof and gutters clear, dead branches gone, trees 10 feet from chimneys. Most of this is already law.
- Phase 1, within 3 years.Nothing burnable in the first 5 feet: no mulch, wood chips, firewood or dead leaves. Clear under decks.
- Phase 2, within 5 years.Plant-free strips by walls, windows, vents and decks. Noncombustible fence sections where fences meet the house. Sheds in the first 5 feet made noncombustible. In State Responsibility Areas, CAL FIRE may set as few as 3 years. In local areas, your fire agency sets 3 to 5 years.
It is about the ground and things attached to the house. Not siding, not garage doors.
A 2025 law lets the Board adopt Zone 0 as an emergency rule, and lets local fire agencies approve alternatives with a similar effect [20]. The Board's next meetings are November 4-5 and December 8-9.
Want an email when it moves? Zone Zero Guidelines tracks every Zone 0 item.
What insurers and IBHS ask for
Wildfire Prepared Home works like this. You apply, a third-party evaluator checks the house and the first 30 feet, and if it passes you get a certificate to show insurers. It costs $125 and lasts 3 years, with photo check-ins after years 1 and 2 [7].
In June 2026 the two levels were renamed: Essential (was Base) and Enhanced (was Plus) [21].
- Essential: bare first 5 feet with no exceptions, Class A roof, noncombustible gutters, ember-resistant vents or 1/8 inch mesh, bottom 6 inches of walls noncombustible, cleared under decks, defensible space to 30 feet [7][5].
- Enhanced adds: enclosed noncombustible eaves, noncombustible siding, dual-pane tempered windows, noncombustible decks, sheds 30 feet away [5].
What some insurers have said
- State Farm (pending): filed September 18, 2026 to write Enhanced homes statewide, and Essential homes in low and moderate zones. Not open for new business yet [22].
- AAA (CSAA): a Wildfire Prepared Home won't be non-renewed for wildfire risk, for at least 3 years [23].
- Mercury: 22.5% to 37.5% off the wildfire part of the premium for a Wildfire Prepared Home, 30% to 50% for Plus (now Enhanced). It says the work does not guarantee eligibility [24].
- FAIR Plan (the state's insurer of last resort): up to 16.4% off the wildfire part since November 15, 2025. No Wildfire Prepared Home discount [25].
The 1% reality
Every insurer must offer discounts for the state's list of actions, including the 5-foot zone [15][16]. But on average, the 5-foot items each take off 0.5% to 1% of the full premium. Wildfire Prepared Home averages 3.8% [26]. In that study, that worked out to about $9 to $14 for each 5-foot item and about $57 for Wildfire Prepared Home.
Doing the work does not guarantee you a policy. You can ask your insurer for your wildfire risk score and how to lower it [16]. Insurance checklist.
Our take. Do the first 5 feet to stay insurable, not for the discount. The discount is small. A non-renewal is not.
What it means for you
- Find out if you are in a State Responsibility Area. If yes, the 100 feet is law today. Check my address.
- Start with the easy part: roof, gutters, dead plants, firewood. What to clear.
- Then clear the first 5 feet. Insurers look for it now, and Zone 0 would require it.
- Replacing a garage door, vents or siding? Ask for parts that meet the WUI code.
Sources
- California Public Resources Code section 4291 (2025 code, as amended by AB 1455), via Justia.
- California Government Code section 51182, via Justia.
- California Public Resources Code section 4291.1, via GoCodebook.
- 2025 California Wildland-Urban Interface Code, section 504.9.2, Garage door gaps, via GoCodebook.
- IBHS, Wildfire Prepared Home Technical Standard, Summary of changes, December 2025 (PDF).
- California Insurance Code section 678, via public.law.
- IBHS Wildfire Prepared Home, Frequently asked questions.
- Office of Administrative Law, Recent actions taken on emergency regulations (file 2026-0828-03E, Zone 0 Defensible Space: withdrawn September 8, 2026).
- California Code of Regulations, Title 14, section 1299.03, Defensible space requirements, via Justia.
- SB 504 (Chapter 982, Statutes of 2024), via Digital Democracy.
- Permit Sonoma, Fire hazard severity zones.
- Legislative Analyst's Office, Reducing the Destructiveness of Wildfires: Promoting Defensible Space in California, September 30, 2021 (2019-20 figures).
- Permit Sonoma, Hazardous vegetation inspections FAQs.
- California Civil Code section 1102.19, via GoCodebook.
- California Department of Insurance, Safer from Wildfires.
- California Department of Insurance, FAQ on the Safer from Wildfires regulation (PDF).
- State Fire Marshal, proposed changes to the Wildland-Urban Interface Code, 15-day express terms, May 18, 2026 (PDF).
- IBHS Wildfire Prepared Home, About.
- Board of Forestry and Fire Protection, Summary of Zone 0 regulations and rule text, August 2026 (copy hosted by UC ANR, PDF).
- AB 1455 (Chapter 731, Statutes of 2025), via Digital Democracy.
- IBHS news release, June 9, 2026: Essential and Enhanced levels.
- California Department of Insurance, "Major California home insurers move to reopen for new business, including state's largest insurer," September 18, 2026.
- CSAA Insurance Group (AAA), Wildfire mitigation resources.
- Mercury Insurance, California wildfire mitigation discounts.
- California FAIR Plan, Discounts for Dwelling Fire and Commercial policies, November 15, 2025 (PDF).
- Ludington, Liao and Walls, From Risk to Reward: Insurance Discounts for Wildfire Mitigation, Resources for the Future Working Paper 25-30, December 2025 (PDF).
Rules change. Sources last checked October 18, 2026. General information, not legal or insurance advice. Your city or county may have stricter rules.