What are Class 4 impact resistant shingles?
Short answer. Class 4 is the highest UL 2218 rating: the shingle survives a 2 inch steel ball dropped from 20 feet onto the same spot twice without cracking. Class 4 shingles, often made with rubberized SBS asphalt or reinforced mats, resist hail better and can qualify for insurance credits with some carriers, though they are not hail proof.
How they are built
- SBS modified asphalt: a rubberized asphalt that flexes on impact instead of cracking, and stays more pliable as it ages.
- Reinforced mats or backing: a stronger fiberglass mat or added layer that resists fracturing.
- Thicker construction overall, so they weigh more than standard shingles.
From the street, most look just like standard architectural shingles.
Benefits in Georgia
North Georgia gets most of its hail in spring and early summer. A Class 4 roof is more likely to come through common hailstorms without functional damage, which can mean fewer claims and fewer deductibles. Some insurers offer a premium credit for Class 4 roofs, and they may ask for an invoice or certificate as proof. Class 4 shingles are also part of the IBHS FORTIFIED hail supplement.
Limits to understand
- Very large hail can still damage them.
- Hail can knock granules loose even without cracking the mat.
- Manufacturers do not warrant hail performance, and their limited warranties exclude hail damage.
- Vents, gutters and flashing can still dent.
- Ridge caps should be Class 4 as well, or they become the weak point.
Is it worth it?
It depends on the price difference for your roof, your carrier's credit, and how often your area gets hail. Robust Roofing walks through that math in its guide on whether Class 4 shingles are worth it in Georgia.
See impact resistant shingles in Georgia and Georgia hail season.