Three questions that a single “fire rated” phrase can conceal
The IBHS/RICOWI guide, section 1.4.3, discusses exterior exposure testing under ASTM E108 and UL 790 separately from foam flame-spread testing under ASTM E84. It identifies roof slope, material thicknesses, and deck combustibility as relevant to exterior classifications.
| Question | Evidence category | Do not infer |
|---|---|---|
| How does the specified roof covering respond to exterior fire exposure? | Applicable ASTM E108 / UL 790 classification and assembly | That every deck and coating combination shares the result |
| What are the foam’s tested surface-burning characteristics? | Applicable ASTM E84 documentation | That a flame-spread index is an exterior roof classification |
| What protection is required inside the building? | Applicable interior assembly requirements and approvals | That an exterior roof coating automatically qualifies as an interior thermal barrier |
A real specification illustrates the boundary
The May 2026 Gaco S20/SPF specification describes Class A, noncombustible-deck requirements in its summary. Later, its foam-product note expressly distinguishes exterior roof-composite fire testing from interior thermal-barrier use. Reading only the first “Class A” reference would omit that important limitation.
This is an annotated specification example, not verification of a particular listing for your roof. A specification’s general description must be checked against the actual applicable approval and installed configuration. Nor does a manufacturer example establish which code edition or requirements apply to a particular NY/NJ building.
Use an assembly identity card
Ask the project team to identify the approval or listing, revision, test classification, deck type, allowed slope, foam product and thickness, protective coating, any required granules, and relevant limitations. Then record the corresponding proposed item alongside each field.
Illustrative mismatch: a summary sheet describes a noncombustible-deck configuration, but the project contains a combustible deck. That is an unresolved applicability question—not something solved by using the same white coating. The designer and manufacturer must establish the appropriate configuration and documentation.
Why the language matters to owners
“Fireproof,” “Class A foam,” and “fire-rated roof” can collapse different claims into one phrase. Ask which component or assembly was tested, under which method, and within what limitations. An accurate answer may be longer than the sales label, but it gives the owner something that can be checked.
Do not use this guide to design an assembly, assess a fire-damaged building, or select interior protection. Those decisions require the appropriate qualified professionals and authority review. The goal is to recognize missing documentation before the proposal is accepted.
Connect the evidence to handover
Preserve the approved submittal with product records and installation evidence in the completion package. Substitutions and later alterations need review rather than an assumption that the original classification continues unchanged. Discuss the exterior SPF roof system separately from interior roof-deck insulation.