IBHS

IBHS Wildfire Prepared Home: the fencing standard insurers actually check

Fact-checked August 19, 2026·Sources at the end of this article

What IBHS is, and why its fence rule carries weight

Wildfire Prepared Home is a voluntary IBHS designation, a whole-home wildfire mitigation standard with a published technical checklist. It is offered in fourteen states: Arizona, California, Colorado, Florida, Idaho, Montana, Nevada, New Mexico, Oklahoma, Oregon, Utah, Texas, Washington, and Wyoming.

Its standard is grounded in field research. After the January 2025 Palisades and Eaton fires, IBHS surveyors walked the burn areas. On the parcels they examined, more than 95% had a fence. Most of those fences (about 65%) were wood, and roughly six in ten were either attached to the home or stood inside the first five feet. That is the picture the fencing requirement is written against.

California already requires carriers that price wildfire risk to credit noncombustible fencing within five feet of the home (more below). But when a carrier wants a single yes-or-no signal that a home is hardened, several point at the IBHS designation. That is what makes its fence text worth reading closely.

The fencing requirement, in the standard’s own words

One sentence carries it, and it sits at the Base level rather than in an upgrade tier:

"Shall remove combustible fencing materials (e.g., wood and vinyl), posts, gates, and retaining walls within 5 feet or replace with noncombustible material."

IBHS Wildfire Prepared Home Technical Standard, December 2025 version, effective June 1, 2026, Section 2.2.1. We read this in the published PDF on August 21, 2026.

Read what it actually names. Not just fence panels: posts, gates and retaining walls too, and vinyl is called out beside wood. The test is on the material, which is why the standard's checklist introduces its examples with "noncombustible materials such as" rather than a closed list. Masonry, brick, stone and concrete are noncombustible and satisfy it just as metal does.

Note what IBHS did not do. No US code contains a fire test for a complete fence assembly, so no fence product can honestly be sold as "certified fire-resistant" as a finished fence. IBHS sidestepped the marketing question entirely by testing the material instead, which is also how the State Fire Marshal came to list a fence product at all. Our guide to noncombustible fence materials covers what passes and what does not.

The Plus tier: back-to-back fences

The designation has a higher tier, Wildfire Prepared Home Plus. For fencing, Plus adds one rule: back-to-back combustible fences closer than five feet apart are barred. Two wood fences running back to back, the arrangement that often appears along a shared property line, can fail the Plus checklist even where a single fence would not.

What carriers attach to the designation

The figures below are the carriers' own published numbers. They are not a promise of what any individual homeowner will save.

Mercury publishes tiered wildfire mitigation discounts of 12.5%–45% on the wildfire portion of premium, and its checklist names "non-combustible fencing or gate materials where they attach to the home." Within those tiers, Mercury puts the IBHS designation at 22.5%–37.5%, and the Plus tier at 30%–50%. Mercury is also plain about the limits:

Do wildfire mitigation efforts guarantee coverage? No. Eligibility and renewal decisions are subject to underwriting review.

Mercury Insurance, California wildfire mitigation page.

AAA / CSAA ties something arguably more valuable than a discount to the designation: a renewal commitment. With IBHS Wildfire Prepared Home certification, CSAA states:

your single-family homeowners policy won't be non-renewed due to wildfire risk and we will renew your homeowners policy for a minimum of three years if you maintain the certification and all other requirements of your policy.

CSAA Insurance Group, wildfire mitigation resources.

In a market where the FAIR Plan has grown by more than 150% in three years, a written three-year renewal commitment addresses the thing homeowners actually worry about: staying covered at all.

Farmers has published no fence-named discount we can verify. But researchers Kousky and You, reviewing filed underwriting criteria, reported that "currently Farmers only insur[es] homes in areas of high fire risk (as measured by zone, slope, and fuels) if they are IBHS WPH+." That is the researchers' reading of filed criteria, not a carrier statement. If accurate, though, it makes the Plus designation something more than a discount in some high-risk areas: a condition of eligibility.

For scale: a Resources for the Future review of every California rate filing from January 2022 through June 2025 found the average maximum property-level discount was about 5.65%, roughly $98 per year. Mercury and CSAA are outliers on the high side, and the fence line item alone typically runs 0.5%–1.2%. Our discount guide breaks down who publishes what.

Stricter than the state's insurance list. Stricter than San Diego.

California's "Safer from Wildfires" regulation (10 CCR §2644.9, operative October 14, 2022) requires any insurer pricing wildfire risk to credit enumerated mitigation measures. The fencing measure, the first of twelve on carrier certification forms, credits "incorporation of only noncombustible materials" into improvements, including fences and gates, within five feet of the building. It is a rating regulation: it binds insurers to offer a credit, and it requires nothing of homeowners. It also publishes no product list.

San Diego's Zone 0 guidelines for existing structures (rev. April 22, 2026, and by their own terms not enforceable until February 28, 2027) are genuinely more permissive on materials than the ordinance itself, which names no fence material. They allow existing vinyl within five feet in defined configurations (parallel to the structure, at least four feet off it, kept free of debris and vegetation) and allows new parallel wood fencing if it is fire-retardant treated wood (FRTW) listed in the OSFM WUI Products Handbook. Neither vinyl nor FRTW is metal or concrete, so neither makes the IBHS checklist. A fence line that satisfies San Diego's Zone 0 ordinance can still fail IBHS.

The statewide regulation (approved by the Board of Forestry on August 19, 2026, and not yet in effect) sits in between. It requires a five-foot noncombustible span where a fence attaches to or comes within one foot of the structure, and, once the regulation takes effect, it bars new combustible fences within five feet. The two tracks are not worded alike. In the Local Responsibility Area (LRA) text, which covers Very High Fire Hazard Severity Zones, that ban expressly reaches new fences and gates "whether attached or parallel to the Occupied Structure." The State Responsibility Area (SRA) version is a single paragraph with no parallel clause, so the explicit parallel-fence ban should not be attributed to it. Under either track, existing combustible fences that pass through the zone unattached may remain. IBHS makes no such allowance: all fencing materials within the zone must be noncombustible, existing or not.

The takeaway: IBHS is the ceiling. Build the fence line to its checklist and you have also met the §2644.9 materials measure, San Diego's fencing provisions, and the fence text of the statewide regulation as written. One caveat on that last item: the August 19, 2026 package published in the board binder is the pre-meeting deliberative draft, and no certified "as adopted" text has been published yet, so treat the exact provision wording as pending. The full California Zone 0 fencing guide maps these against each other.

What pursuing the designation means for your fence line

The fence item is one of the clearest pass/fail checks in the standard. Working through it looks like this:

• Walk the first five feet. Every fencing material inside the zone (fence panels, gates, both sides of a corner) must be metal or concrete. A wood or vinyl gate within five feet of the house is a fail, even on an otherwise metal run.
• Check posts and footings, not just panels. A metal panel hung on a wood post fails the intent. The same goes for gate hardware, latches, and wood blocking where the fence meets the wall. Our guide to the five-foot noncombustible transition covers the details at the attachment point.
• For Plus, look at fence pairs. Back-to-back combustible fences closer than five feet apart are barred, which can mean a conversation with a neighbor before you apply.
• Document as you go. The aerial imagery models many carriers use to score wildfire risk cannot see a fence. Photographs, receipts, and material specs are how the improvement actually gets counted, by IBHS and by your carrier. Our documentation guide shows what to capture.
• Check incentives before you start. IBHS maintains a state-by-state list of designation incentives (linked in the sources below).

A fence can pass the state rule and still fail IBHS

These two rulebooks are often described as if they line up. They do not, and the gap runs one way: IBHS is stricter than the adopted state regulation on exactly the point most homeowners care about. A wood fence that satisfies California can still cost you the designation.

The requirement is one sentence, and it is in the Base level, not an upgrade:

"Shall remove combustible fencing materials (e.g., wood and vinyl), posts, gates, and retaining walls within 5 feet or replace with noncombustible material."

IBHS Wildfire Prepared Home Technical Standard, December 2025 version, effective June 1, 2026, Section 2.2.1

Section 1.1.1 states that "The Home – Plus (Enhanced) level builds upon the Home – Base (Essential) level requirements", so there is no IBHS designation at any level that tolerates a combustible fence in the first five feet.

None of this is law, and that distinction is the whole point. IBHS is a private research organization funded by insurers. Its standard is a contract term in a voluntary program: no California agency enforces it, no inspector cites it, and the direct consequence of falling short is that you do not get or keep the designation. Section 1.1.1 puts the mechanism plainly: "To earn a designation, a property shall meet all the requirements for the chosen designation level, as evaluated by an authorized third-party, and verified by IBHS."

The reason it is worth your attention anyway is that a carrier can choose to care about it. Where an insurer ties eligibility or pricing to the designation, the practical requirement on your fence is the IBHS one, not the state one, and it arrives years before any state deadline. That is the honest answer to "will I have to replace my wood fence": not because of the state rule, not yet, but possibly because of who insures you. We cover what carriers actually publish, including the one reported case of a carrier conditioning high-risk coverage on the designation, and the hedges that belong on it.

What this means for you

If you are pursuing the designation, the fence line is a fixed target: metal or concrete within five feet, no exceptions for products marketed as fire-resistant. There is no partial credit on this item.

If you are not pursuing it, the same five feet is still the highest-leverage span of fence you own. It is the subject of the first measure on the twelve-item mitigation form California requires your carrier to honor, and the statewide regulation adopted on August 19, 2026 requires a noncombustible span at the attachment point once it takes effect.

Be clear about what is not required. The statewide regulation approved on August 19, 2026 is not yet in effect, so no statewide rule requires you to replace any fence today, and the IBHS standard is voluntary: a designation you choose to pursue, not a mandate. Only local ordinances impose Zone 0 requirements right now, in at least thirty-five jurisdictions, each with its own scope. What the designation offers is the strongest documented link between fence work and insurance outcomes on the table. Mercury publishes discount tiers, and CSAA puts a three-year renewal commitment in writing. Per one research team's reading of filed criteria, at Farmers in some high-risk areas the designation is eligibility itself.