Impact resistant shingles are evaluated in terms of lab tests. The test verifies that a product can sustain impact from either a steel ball dropped from a specified height, or ice projectile shot from an ice cannon without resulting in product failure. Many insurance companies reward their customers with a premium discount if this type of product is installed. You will need to check with your agent to determine the amount of discount you will receive.
There are several types of impact resistant shingles on the market. A Class 3 shingle (tested with 1.75” projectile) is less expensive than a Class 4 (tested with 2” projectile) and will in many cases provide you with a premium discount. Some Class 4 product meets this classification, but the product simply has a scrim on the back of the shingle preventing a blow through. Other Class 4 products are reinforced with a polymer that changes the composition of the shingle to make it more durable. It is important to know that not all Class 4 products are created equally.
