Impact “Resistant” is not Impact “Proof!”
Folks in central Oklahoma have been hit with waves of hailstorms over the past decade. Some homeowners have installed three roofs over the past 5 years alone. Because “necessity is the mother of invention”, there has been a wave of “impact resistant” roofs introduced into the market.
These shingles are generally rated as Class 4 and have been tested under conditions that are supposed to emulate a hailstorm. One group uses a test that drops a 2” steel ball from 20 feet in the air to see if a shingle is damaged. Another group uses ice balls taken from a freezer and then those ice balls are fired out of a “hail gun” at a shingle. Either way, once a shingle passes the appropriate test and gets a Class 4 rating, they are called “impact resistant.”
Make no mistake, these are tougher shingles and they are going to withstand a standard nickel, dime, quarter, size hail stone better than most standard shingles. But, it is important to recognize these are not rated “Impact PROOF!” In the simplest sense, think of hailstone falling from the sky. They are not perfectly round and often have jagged edges. They greatly vary in density from one storm to the next. Some are slushy and explode on impact and others have been known to pass through the roof decking and hit the ceiling inside a home. Some come in at 50 mph, by example, and others could be doing 100 mph based on type of storm and speed of the wind.
In other words, if it is a large hailstone coming in like a baseball, the “resistance” may not be enough to weather the storm. If you want an “impact proof” roof, you may have to live underground or install a steel dome around your house. Again, “impact resistant” shingles are very worthwhile (we install a lot of them and some insurance companies even lower your premiums when they are installed). These shingles may get you through several hailstorms without a claim. Yet, when the big ones fall, just remember they are impact resistant, not impact proof.