9.1 Asphalt Shingles: Types, ASTM D3462, Wind Classes, Impact & Fire Ratings
Key Takeaways
Under R905.2.4, asphalt shingles must comply with ASTM D3462, the standard for fiberglass-mat shingles surfaced with mineral granules.
Asphalt shingles must be tested to ASTM D7158 and labeled with the class required for the design wind speed, or labeled to ASTM D3161 if they fall outside D7158's scope.
At ultimate design wind speeds of 110 to 116 mph, which covers typical Michigan sites, the code accepts ASTM D7158 Class D, G, or H or ASTM D3161 Class A, D, or F.
UL 2218 impact classes run from Class 1 to Class 4, and Class 4 shingles withstand a 2-inch steel ball dropped from 20 feet.
Michigan requires classified (Class A, B, or C) roofing only where a law designates it or where the roof edge is less than 3 feet from a lot line.
How an Asphalt Shingle Is Built
Modern shingles have a fiberglass mat saturated and coated with asphalt. The top is surfaced with ceramic-coated mineral granules that protect the asphalt from UV, color the shingle, and help with fire resistance. A factory-applied sealant strip bonds each course to the one below when the sun warms it. Algae-resistant shingles use granules with metal additives to slow the black streaks caused by algae.
| Type | Construction | Typical traits |
|---|---|---|
| 3-tab (strip) | Single layer with cutouts forming three tabs. English size about 12 × 36 inches at a 5-inch exposure | Lightest and least expensive, with a flat look |
| Laminated (architectural or dimensional) | Two or more layers bonded together, often in metric size about 13 1/4 × 39 3/8 inches at a 5 5/8-inch exposure | More texture and weight, and usually higher wind warranties |
| Designer and luxury | Heavier multi-layer shingles that imitate slate or shakes | Heaviest. Check the structure and bundles per square |
The Material Standard (R905.2.4)
Asphalt shingles must comply with ASTM D3462, the specification for shingles made from glass felt and surfaced with mineral granules. The standard covers properties such as mass, tear strength (at least 1,700 grams), fastener pull-through, and pliability. Old organic-mat shingles, formerly covered by ASTM D225, are no longer made for the market. You will still see them on tear-offs. They curl and blister as they age.
Wind Resistance (R905.2.4.1)
Asphalt shingles must be tested to ASTM D7158 and meet the classification in Table R905.2.4.1 for the design wind speed. The packaging must carry a label showing D7158 compliance and the class. Shingles outside the scope of D7158 must be tested and labeled to ASTM D3161 instead.
| Ultimate design wind speed, V_ult (mph) | Basic wind speed, V_asd (mph) | ASTM D7158 class | ASTM D3161 class |
|---|---|---|---|
| 110 | 85 | D, G, or H | A, D, or F |
| 116 | 90 | D, G, or H | A, D, or F |
| 129 | 100 | G or H | A, D, or F |
| 142 | 110 | G or H | F |
| 155 | 120 | G or H | F |
| 168 and up | 130 and up | H | F |
Michigan's design criteria list a 90 mph basic wind speed. That corresponds to the 116 mph row, so any listed D7158 class (D, G, or H) or D3161 class (A, D, or F) is acceptable for typical Michigan sites. D7158's calculations assume Exposure B or C and buildings no taller than 60 feet. Lakeshore or unusually exposed sites need a site check. Manufacturers' high-wind nailing and sealing instructions also affect warranty coverage.
ASTM D7158 compares the wind uplift force on a sealed shingle with its measured resistance. The classes are D (90 mph), G (120 mph), and H (150 mph). ASTM D3161 is a fan-driven test at set wind speeds: Class A (60 mph), D (90 mph), and F (110 mph).
Impact Resistance (UL 2218)
Hail is common in Michigan's summer storms. UL 2218 drops steel balls on the same spot twice. The product passes if no crack or rupture appears.
| UL 2218 class | Steel ball diameter | Drop height |
|---|---|---|
| Class 1 | 1 1/4 in | 12 ft |
| Class 2 | 1 1/2 in | 15 ft |
| Class 3 | 1 3/4 in | 17 ft |
| Class 4 | 2 in | 20 ft |
The code does not require impact ratings. Owners may want Class 4 shingles for durability or possible insurance discounts. Confirm any discount with the owner's insurer rather than promising one.
Fire Classification (Michigan R902.1)
Roof coverings are fire-tested under UL 790 or ASTM E108:
- Class A: effective against severe fire exposure.
- Class B: effective against moderate fire exposure.
- Class C: effective against light fire exposure.
Michigan's R902.1 requires Class A, B, or C roofing only where local law designates it or where the roof edge is less than 3 feet from a lot line. Most fiberglass asphalt shingles are Class A rated when installed as listed. Check the package and the manufacturer's listing when a classification is required.
Product Identification, Handling, and Compatibility
- R904.4: roof covering materials must be delivered in packages bearing the manufacturer's identifying marks and the testing agency labels required, including the wind class label. Bulk shipments need the same information on a certificate or bill of lading. Keep a wrapper for the inspector.
- R904.2: materials must be compatible with each other and with the building.
- R904.1 and R905.1: install per this code and the manufacturer's instructions.
- Storage: store bundles flat, off the ground, covered, and out of extreme heat or cold. Do not stack bundles so high that the lower ones deform. In cold weather, shingles become stiff and crack more easily. Many manufacturers require hand-sealing when temperatures prevent the sealant from activating.
Choosing a Shingle for a Michigan Job
- Confirm the slope: at least 2:12, with double underlayment below 4:12.
- Confirm the wind class label and any site exposure issues.
- Confirm weight against the structure and snow load, especially on a recover (R908.2).
- Match the manufacturer's system components if the owner wants an enhanced warranty.
- Consider impact class, algae resistance, color and heat, and matching existing roofs on additions.
Which ASTM standard does the 2015 MRC require asphalt shingles to meet?
ASTM D226
ASTM D1970
ASTM D3462
ASTM C1289
For a typical Michigan site at a 90 mph basic wind speed (about 116 mph ultimate), which shingle wind labels satisfy Table R905.2.4.1?
ASTM D7158 Class D, G, or H, or ASTM D3161 Class A, D, or F
Only ASTM D7158 Class H
Only ASTM D3161 Class F
No wind label is required at this wind speed
Under UL 2218, what test does a Class 4 impact-resistant shingle pass?
Two impacts in the same spot from a 2-inch steel ball dropped 20 feet without cracking or rupture
A 1 1/4-inch steel ball dropped 12 feet
A 1 3/4-inch steel ball dropped 17 feet
A 110 mph fan test for 2 hours
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