Class 4 Impact-Resistant Shingles in New Jersey

What “Class 4” Actually Means

Class 4 isn't a marketing word — it's the top tier of a specific lab test called UL 2218. In that test a steel ball of a fixed weight is dropped onto the shingle from a fixed height, twice on the exact same spot, and then the back of the shingle is inspected for cracks in the mat. If it splits, it fails the grade.

The rating runs in four tiers, Class 1 through Class 4, with Class 4 being the heaviest drop a shingle can take without the mat fracturing. Here's the part most homeowners don't realize: a standard architectural shingle usually carries no impact rating at all. Class 4 is a deliberately built-up product, not a premium version of the same thing.

The difference is in the asphalt. A standard shingle uses fairly rigid asphalt that cracks once something hits it hard. A Class 4 shingle uses a modified asphalt — usually SBS, the same rubberized chemistry as self-adhering ice-and-water membrane — that flexes and absorbs a blow instead of shattering. Bend a rubber band and it springs back; snap a dry twig and it breaks. That's the whole idea.

Why This Matters in NJ Right Now

This used to be a niche product. It isn't anymore, and the reason has nothing to do with the weather and everything to do with your insurance bill. New Jersey homeowners are getting squeezed: carriers are non-renewing policies on older roofs, and others are quietly moving aging roofs from replacement-cost coverage to ACV — actual cash value, which pays the depreciated value of a worn roof, not the cost to replace it. We cover how that plays out in our piece on roof age and insurance non-renewal in NJ.

Here's the flip side of that pressure. Because a Class 4 roof is statistically less likely to generate a hail or impact claim, many NJ carriers credit it with a premium discount. We have to be careful how we frame this, because it varies a lot: some carriers offer a meaningful discount, some offer a small one, and some offer nothing. We will never quote you a percentage — that's between you and your insurer.

The right move is to call your agent and ask two questions: does my carrier credit a verified Class 4 roof, and what documentation do you need to apply it. If the answer is yes, a Class 4 re-roof can shave your premium every year for the life of the roof. We give you the manufacturer certification and a photo-documented report to submit. If you're already mid-claim or fighting a coverage change, our insurance claim help page walks through how we document for carriers.

Are They Worth It in New Jersey? Our Honest Take

We'll give you the straight version, because the honest answer isn't the same for every house. New Jersey gets wind and the occasional hailstorm, but we are not Texas hail alley. If pure hail survival were the only argument, the upgrade would be hard to justify here. It isn't the only argument.

The real case in NJ is two things working together: insurance economics and longevity. The rubberized asphalt that helps a Class 4 shingle survive impact also keeps it flexible through our freeze-thaw winters, where rigid shingles get brittle and crack. A tougher shingle that also earns a yearly premium credit is a different math problem than “will it stop hail.”

The Products We Install

As a GAF Certified roofer, we install GAF's Class 4 impact-resistant lines — including the Timberline AS II, GAF's SBS-modified Class 4 shingle — along with equivalent UL 2218 Class 4 systems where they fit the job better. They look like a standard architectural shingle from the curb, so you aren't trading appearance for toughness.

One thing we're strict about: a Class 4 shingle only earns its rating and its warranty when it's installed as a complete system — the right underlayment, properly sealed valleys and penetrations, and balanced attic ventilation so the deck doesn't cook the shingles from below. We install the full GAF system, not just the top layer, so the manufacturer warranty stays intact and the impact rating means something on your roof.

Pairing Class 4 With a Re-Roof

The smart time to go Class 4 is when you're replacing the roof anyway. Tearing off and re-decking is the expensive part of any roof replacement; the jump from standard architectural to Class 4 shingles is an incremental upgrade on top of work you're already paying for. On its own, as a tear-off just to get the rating, the case is much weaker.

On cost — and we don't publish numbers, because every roof is different — a Class 4 shingle carries a premium over standard architectural at the material level. That premium gets offset two ways: the annual insurance credit if your carrier offers one, and the longer service life of a more flexible shingle through NJ winters. Whether the math works depends on your carrier's discount and how long you plan to stay. We'll lay both sides out in writing before you decide.

This ties directly into the roof-age question driving so many NJ insurance headaches. If your roof is old enough to worry your carrier, a Class 4 replacement fixes two problems at once — it resets the roof's age and may qualify for a discount. If you're weighing a claim versus paying out of pocket, our explainer on whether homeowners insurance covers roof replacement in NJ is the right place to start.

Class 4 Impact-Resistant Shingle FAQs