Class 4, impact-resistant roofing shingles: Everything you need to know

If you live in an area where storms and hails are a common thing then you might be interested in this article. We are going to talk about class 4, impact-resistant shingles that will protect your roof under harsh conditions. Let’s break down everything and make it easy for you.

What is class 4 impact resistance?

Class 4 impact resistance is the highest resistance that a shingle can tolerate. Under lab testing, if a 2-inch ball is dropped from 20 feet and the new shingle survives it without splitting or tearing then it has a resistance of class 4.


Class 4, impact-resistant roofing shingles:

Impact-resistant roofing shingles also called IR roofing shingles are the shingles that provide extra protection to your roof during storms and harsh weather conditions. Not only do they benefit you by protecting against harsh weather but also help you gain a discount on your home insurance. Whether it’s hail, storm, or heavy rain, the high resistance of these shingles don’t let your roof get damaged.

Here is all you need to know about class 4, Impact resistant shingles.

  • Designed to give strength and durability to your roof:

Impact-resistant roofing shingles are designed in this way that gives your roof extra strength, especially if your house is somewhere where storms come frequently. Non-impact roofing shingles can be easily damaged when struck by debris and hail during storms. This advancement is the result of continuously improving the previous asphalt shingles. Now you can live in areas where there are storms without the risk of getting your roof destroyed.

There are two ways through which impact-resistant shingles are designed and engineered.

  • Reinforcing, polymer-based mesh:

One way through which high-resistance shingles are made is by reinforcing polymer-based mesh to the back of the standard asphalt shingle. This mesh is added embedded in a way to the shingle that holds the shingle together during harsh weather and doesn’t let it split.

  • SBS (styrene-butadiene-styrene):

SBS or rubber-like polymers are integrated with the asphalt shingle. Due to the mixing of asphalt and this rubber-like polymer, the shingle becomes more flexible and more rubber-like. Due to this, it can tolerate the impact of being struck by debris or any other thing during harsh weather.

Why are they needed?

Due to heavy storms in the USA during the 1990s industries started testing out the shingles they were producing. They ultimately came with class 4, impact-resistant roofing shingles when they saw the mix of other materials in it, the shingles can tolerate the impact better.

They also came up with the test which is called Underwriters Laboratory 2218 (UL2218) and is most commonly known as the steel ball test. In this test, the steel ball is dropped on the shingle several times and the shingle is tested whether or not it was able to endure that impact.

Other classes for shingles:

Many other classes exist for shingles other than class 4. The difference between class 4 and other classes is that class 4 steel balls are 2 inches and I dropped from a height of 20 feet while other classes have steel balls that are smaller in size. Mainly, class 3 and class 2 exist.

Wind resistance of class 4 roofing shingles:

There is a clear difference between wind resistance and another type of resistance that occurs when two objects are rubbed together. People often confuse wind resistance with other resistance. We here, want you to know that class 4 roofing shingles do not have high wind resistance or we can say that their wind resistance is not as high as the other resistance.

Benefits of installing class 4 impact resistant shingles:

There are many benefits of installing class 4, impact-resistant shingles.

Reduce or eliminate the need for roof repairs:

Strong shingles like these will eliminate your worry to get our roof repaired. It will easily tolerate heavy storms without you getting worried about your roof. Ultimately, it will save you a lot of money which you might need to spend if you don’t have these shingles on your roof. Even if it doesn’t eliminate the need for repairing, it’ll for sure reduce the frequency of it.

Insurance discount:

You’ll get a discount on the insurance of your home if you have class 4 shingles installed on your roof. It will give you roof and home protection and will increase its value of it.

Extended lifespan of your roof:

It’ll also extend the lifespan of your roof as these shingles will protect it and they are not prone to damage. Many contractors give a warranty of 50 years for these shingles. Some of the features that class 4, impact-resistant shingles have are:

  • They have a class A fire rating.
  • They significantly reduce the risk of interior damage due to roof leaks.
  • They resist the wind speed of 110 mph or higher.
  • They protect the roof against flying debris and hail.


Cost of the shingles:

The cost of these shingles is higher than other shingles that do not provide your roof with such protection. SBS class 4; impact resistant shingles have a cost that is 10 to 15 percent higher than asphalt shingles. You can make up for this high cost as you won’t need to replace the roof for a long time and also your repair costs will be saved.

The best class 4, impact-resistant roofing shingle material:

One of the materials that you can go for and which offer you the beauty of Spanish clay is a lightweight synthetic-composite shake.

Synthetic-composite shake is composed of fiberglass, asphalt, and other materials that are sustainable and make the shingle strong. These materials are eco-friendly and provide your roof with a long life. As compared to other materials such as clay, concrete, slate, and cedar tiles, these look more aesthetically pleasing.


Class 4 impact-resistant roofing shingles are a perfect choice for any kind of roof. They can prevent your roof from any kind of damage and they don’t only give benefit only to your roof but also to your interior by protecting it from roof leakage and stuff. It might have a cost higher than other shingles but it’ll be covered up by giving less insurance and roof repairing payments.


David - Author

I’m a roof expert. I’ve been in the roofing industry for over 20 years and I know everything there is to know about roofs. The roof is an important part of a building because it protects the interior from rain and snow. It also helps to keep out wind and other weather conditions that could damage the building.

The roof is the outermost part of a building. It provides protection from the elements and from above.