Your Location: Locating... | Change

What is Class 4 Impact Resistance?

Please Note: This blog post was published in the past, and though it has since been updated, may not reflect products currently offered in your region. For current product availability in your area, please visit our Residential Roofing products page and our Where to Buy page for details.

All roofing products go through rigorous testing by independent, nationally recognized laboratories to provide assurance that product performance meets specifications. Impact resistant roof coverings are rated Class 1, 2, 3 or 4, with Class 4 being the most durable. This test is most commonly performed by Underwriter Laboratories, also known as UL.

During a Class 4 impact resistance test on asphalt shingles, a 2” diameter steel ball is dropped from 20’ onto the shingle to simulate the impact of hail. This is done twice in the same spot. This process is then repeated on 6 different spots. A shingle passes the test if it does not show any visible evidence of tearing, fracturing, cracking, splitting, rupture, crazing, or other opening of the roof-covering layer. Malarkey shingles with NEX® Polymer Modified Asphalt tend to resist deformation and granule loss on the face of the shingle, as well as cracking on the underside.

What does this mean for homeowners? While no roofing material is completely hail proof, homeowners in hail prone areas can reduce their risk of impact damage by installing Class 4 shingles. Many insurance companies will even offer a discount for homes with Class 4 shingles.

*Each hail event is different and results may vary. Malarkey does not warrant that the same results will occur on all buildings installed with shingles containing NEX® Polymer Modified Asphalt.


Malarkey Class 4 Impact Resistant Shingles:


Windsor® Scotchgard™


Hail Facts:

  • According to the National Weather Service, on average, only about 3% of all hailstorms produce hailstones over 2” in diameter.
  • The largest hailstone ever recorded in the United States fell in Vivian, South Dakota in July of 2010. It measured over 8” in diameter, weighed nearly 2 lbs., and had a circumference of 18.62”.
  • According to the Insurance Information Institute, United States property damage due to hail reaches nearly $1.25 billion annually.


Hail Resources:

How Modified Asphalt Tackles Extreme Weather Challenges

IBHS Hailstorm Demonstration