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2024 IWUIC Class 3 Class B roof-assembly path

The unamended 2024 IWUIC model code specifies a Class B-or-better tested roof assembly for Class 3 ignition-resistant construction.

This is a model-code path, not a claim of local adoption. A documented roof assembly can match the minimum rating and test; the alternative approved noncombustible covering and all deck, underlayment, profile-space, and amendment checks remain separate.

code · Jurisdictions adopting unamended 2024 IWUIC Chapter 5 · Last verified 2026-08-25 · JSON (CC BY 4.0)

Published requirement text

“not less than a Class B rating when tested in accordance with ASTM E108 or UL 790”

2024 International Wildland-Urban Interface Code, Section 506.2 — International Code Council

Where this instrument is documented

Instrument iwuic-2024.

Set a location to read how this instrument lands where you are.

PlaceForceReachDatedChecks openSource
Clark County active application documented unincorporated county effective 2026-01-01 6 Clark County Ordinance 5320
Jackson active application documented incorporated boundary effective 2025-01-01 5 Town of Jackson Ordinance 1416
Teton County active application documented unincorporated county effective 2025-02-01 6 2024 Teton County Fire Code Resolution
Washoe County active application documented unincorporated county effective 2025-07-01 6 Washoe County Adopted Building Codes

Each place page carries that place's boundary, project scope and open official checks in full; this page's JSON twin carries them per application.

Machine-readable constraints

AttributeOperatorValue
assemblyRole eq roof-assembly
fireRating in class-a–class-b
testStandard in astm-e108–ul-790

Products with documented matching attributes

Open the Build rules that quote this requirement

Sources

2024 IWUIC Class 3 Class B roof-assembly path. FireApproved. https://fireapproved.com/requirements/iwuic-2024-class-3-class-b-roof-assembly/. Last verified 2026-08-25.