Roofing Wind & Fire Ratings Explained (ASTM D3161 / D7158, UL 790)

Wind: ASTM D3161 and ASTM D7158

Asphalt shingles are wind-tested by two ASTM methods:

• ASTM D3161 (fan-induced): specimens are held in a directed air stream for two hours. Classes are A (60 mph), D (90 mph), and F (110 mph) — Class F is the highest and most common on quality laminates.
• ASTM D7158 (uplift force / uplift resistance): the method referenced by the IRC/IBC for asphalt shingles. Classes are D, G, and H, with H the highest. When first published the classes corresponded to roughly 90, 120, and 150 mph basic wind speeds; current editions express those thresholds against ultimate design wind speeds (Vult) to align with modern code, so read the class letter rather than a single mph number.

Both methods assume correct installation; a shingle's rating is only realized when it is nailed and sealed per the manufacturer's instructions. Example cataloged products: GAF Timberline HDZ and Owens Corning TruDefinition Duration publish high wind ratings on their spec sheets.

Fire: UL 790 / ASTM E108

Roof-covering fire performance is graded by UL 790 (equivalent to ASTM E108), which exposes an assembly to flame spread, burning-brand, and (for some classes) intermittent-flame and rain tests. The classes are:

• Class A — severe exposure; the highest rating.
• Class B — moderate exposure.
• Class C — light exposure.

Most quality asphalt, metal, and tile assemblies achieve Class A. In the directory, materials and products list their fire rating on each entry — for instance the clay tile and standing-seam metal material entries note Class A performance, as do most cataloged laminates such as CertainTeed Landmark.

Impact: UL 2218

Impact (hail) resistance is graded separately by UL 2218, a steel-ball drop test, on a 1–4 scale. Class 4 — a 2-inch ball dropped from 20 feet without the underside cracking — is the highest. Because hail is the dominant roofing peril on the Front Range, impact rating deserves its own deep dive: see Class 4 Impact-Resistant Shingles in Colorado and the Class 4 materials hub.

How to read a product's ratings

On any product entry you will see the wind rating (mph), fire class, and — where applicable — the UL 2218 impact class, each with its cited source. Match the fire class to your risk (Class A in WUI zones), the wind class to local exposure, and the impact class to hail exposure. For the material-family tradeoffs behind these numbers, see Asphalt vs. Metal vs. Tile.