Your printed WUI Code book is missing five 2026 amendments

The printed book on your desk isn't the enforceable text

If you're designing or plan-checking in a Fire Hazard Severity Zone, pull your 2025 California Wildland-Urban Interface Code (Part 7) off the shelf. The book you're holding is missing five amendments — and one of them quietly deletes the application-date exceptions that a lot of remodels used to lean on.

Here's the thing: these aren't a rumor or a proposal. The State Fire Marshal adopted them as an emergency building standard, SFM EF 01/25, and they took effect the same day as the 2025 code itself — January 1, 2026. They're printed on the blue "Emergency Supplement" pages that replace Part 7 pages 1-1 to 1-4, 1-15/1-16, 2-1 to 2-4, and 5-3 to 5-6. If those blue pages aren't in your binder, your book is out of date.

And it matters which text you use: Health and Safety Code §18938.5 says only the building standards in effect when the permit application is submitted apply to the project. The enforceable version is the one with the supplement.

(This post is about the amendments, not who's in scope. For the zone-and-building-type mechanics — SRA vs. LRA, additions, accessory structures, the roof-replacement trigger — see Does the WUI code apply to you?.)

The five changes, straight from the supplement

The History Note in the supplement sums them up: amend Chapters 1, 2 and 5 to expand application to High Fire Hazard Severity Zones in Local Responsibility Areas, clarify the application section, define "home hardening," and fix a clerical error on open eaves. In detail, the five items are:

1. §1.1.2 Purpose now reaches High FHSZ in LRA, not only Very High.
2. §101.3.1 and §101.3.1.1 merged into one §101.3.1, and the application-date ("trigger date") exceptions were deleted.
3. A new definition of "Home hardening" was added to Chapter 2.
4. §503.1 lost its exception for pre-2008 additions and remodels.
5. §504.3.1 (open eaves) got a clerical cleanup.

The one to read first: the trigger dates are gone

For years, Part 7's application section keyed compliance to permit-submittal dates. The old §101.3.1.1 said new buildings permitted on or after July 1, 2008 had to comply, with tiered exceptions reaching back to January 1, 2008 and December 1, 2005 — and the old §101.3.1 carved out "additions to and remodels of buildings originally constructed prior to July 1, 2008." §503.1 carried that same pre-2008 carve-out as its own exception.

The emergency supplement deletes all of it and folds everything into a single §101.3.1 that keys application to the zone, not to a date.

Verified against the 2025 WUI Code Emergency Supplement (blue page 1-15) and the State Fire Marshal's approved express terms (SFM EF 01/25, Item 2): the merged §101.3.1 applies to new buildings and their accessory structures on SRA land, on LRA lands the State Fire Marshal identifies as High and Very High Fire Hazard Severity Zones, and on High/Very High or WUI areas designated locally — with four scope exceptions (Group U at 50 ft, Group U agricultural, Group C special per CBC §450.4.1, and accessory structures under §504.11). No permit-date exceptions remain.

What this does not do is make the whole code retroactive — §101.4 and §102.8 still govern existing conditions. It removes the automatic pass that additions and remodels of older buildings used to get. If a project relied on that pre-2008 exemption, re-check it, and confirm the call with your local jurisdiction.

"Home hardening," now a defined term

Chapter 2 gained a definition worth knowing, because the phrase turns up in grant programs and local ordinances:

Verified against the Emergency Supplement (blue page 2-4): "Home Hardening. A method of utilizing construction features, building materials and maintenance practices intended to increase a building and structure's resistance to ignition from fire exposure, including direct flame contact, radiant heat and embers."

The §504.3.1 fix is the small one: the open-eaves materials list dropped a stray "2-inch nominal dimension lumber" entry and renumbered — the History Note calls it a clerical correction.

Where this stands as of today

Emergency standards run on a clock, so date your reliance. SFM EF 01/25 was approved October 15, 2025, filed with the Secretary of State November 4, 2025, and effective January 1, 2026. The Commission readopted it on May 6, 2026 under Government Code §11346.1(h) to keep it in force while the permanent version is certified. That permanent rulemaking — SFM 04/25 — reached its Final Statement of Reasons on July 16, 2026 and was on the Commission's late-August 2026 agenda; once adopted, it publishes as a supplement to the 2025 code effective July 1, 2027. As of this writing (September 22, 2026), the emergency text is what governs — but because the August meeting results weren't yet posted, confirm the current status with the Building Standards Commission before you rely on a date.

What CrossBeam does with it

CrossBeam checks a project against the WUI text that's actually enforceable on the permit date — supplement and all — not just what's printed in the base book. When an emergency amendment changes scope or deletes an exception, that shows up where you're reviewing the plan, in plain language, so a deleted trigger-date carve-out doesn't slip through.