September 2026
Impact resistant shingles get sold hard and explained badly. Here is what the ratings actually test, and when paying more for Class 4 is worth it in a metro that sees hail most springs.
What the rating actually measures
The standard is UL 2218, and the test is blunt: a steel ball is dropped onto the shingle from a set height, and the shingle is examined for cracking on the back side. Class 1 through Class 4 correspond to increasing ball sizes and drop heights, with Class 4 being the two inch ball.
A Class 4 shingle is genuinely tougher against hail. It is not a guarantee hail will never damage your roof.
What matters is what the test does not measure. It tests impact resistance on a new shingle in a lab, not granule retention over twenty years, not wind performance, and not how the shingle behaves at forty degrees versus ninety.
So a Class 4 shingle is genuinely tougher against hail. It is not automatically a better shingle in every respect, and it is not a guarantee that hail will never damage your roof.
One practical note: impact rated shingles are usually heavier and slightly stiffer, which changes how they handle in cold weather installation. It is not a problem, it is something the crew should know going in.
Where it pays off around here
The Mid-South gets hail often enough that impact rating is a real consideration rather than a theoretical one. If you have replaced a roof once because of hail, you already know the math.
The straightforward case for Class 4 is a home you intend to stay in. Over a long enough horizon, the extra cost at installation is weighed against the probability of a deductible plus disruption at some point in the next decade.
The weaker case is a house you plan to sell in three years. The next owner benefits and you paid for it.
If you are staying put, also ask about the warranty terms specifically for the impact rated line, because they sometimes differ from the manufacturer's standard product.
The insurance conversation
Many carriers offer a premium discount for a Class 4 roof. The amount varies a lot by carrier and by policy, and it is worth an actual phone call before you decide, not an assumption either way.
Ask your carrier two things: whether they discount for impact rated roofing, and what documentation they need. Usually it is the manufacturer certification for the specific product installed, which we can provide.
Do not let a contractor tell you what your discount will be. They do not know, and your carrier does.
Worth asking your agent what documentation they want on file, because getting it at installation is easy and getting it three years later is not.
How to choose without overthinking it
If you are replacing a roof anyway and you plan to stay, price both. The difference is often smaller than people expect once it is a line item in front of you rather than an abstraction.
If a contractor is pushing Class 4 hard without asking how long you plan to stay or whether your carrier discounts it, they are selling a product rather than solving your problem.
And if your roof does not actually need replacing yet, none of this is urgent. That is a conversation worth having first.
And whatever you choose, keep the paperwork with the house records. The next owner, or your own claim in year six, will want to know exactly what is up there.
What else affects how a roof survives hail
The shingle is one variable. Roof pitch matters too, because a steeper slope presents a glancing angle to falling hail rather than a flat target, and it is part of why two houses on the same street fare differently.
Age matters enormously. A shingle at fifteen years has lost granule coverage and flexibility, and it bruises at impacts a new shingle would shrug off. Impact rating on an old roof is a historical fact, not a current condition.
Installation matters as much as the product. A correctly nailed shingle that stays sealed down resists wind and impact far better than a premium shingle nailed high and held on by adhesive alone.
So the honest framing is that Class 4 improves your odds within a system. It is not a force field, and anybody selling it as one is overselling.
The page that goes with this
If you have decided the top rating is worth it, the product and the install are covered on Class 4 impact resistant roofing around Memphis.
Questions we get asked
Will Class 4 stop all hail damage?
No. It resists impact better and it still bruises in a severe enough event. It reduces risk, it does not eliminate it.
Is Class 3 a waste of money then?
Not at all. It is a meaningful step up from a standard shingle and it usually costs less than Class 4. It is a reasonable middle.
Does impact rating affect wind performance?
They are separate ratings. A shingle can be excellent at one and ordinary at the other, so look at both if wind is your concern.
How do I know what is on my roof now?
If you have the paperwork from the last replacement it will say. If not, we can usually identify the product from the roof itself.
Do you install both?
Yes, Class 3 and Class 4 both, along with architectural and designer profiles.
What to take from this
UL 2218 tests impact on a new shingle in a lab. It is useful information, not a guarantee.
Class 4 makes the most sense on a house you plan to keep.
Call your own carrier about the discount rather than believing a contractor's number.
If the roof does not need replacing yet, this decision is not urgent.
Get it handled
Jonathan Stephenson answers the phone himself, walks the roof, and gives you a written number. Serving Germantown, TN and the Memphis metro.