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Impact-resistant (Class 4) roofs and hail discounts
What a Class 4 rating tests, which roofs qualify, how insurers and states handle the discount, and the cosmetic-damage catch to check before you upgrade.
A Class 4 roof is a roof covering that passed the toughest level of a standardized impact test, and many insurers in hail country give a premium credit for one. In most states the credit is the insurer's choice, not a legal requirement, and its size varies by company, so the first step is to get the credit in writing before you pay for the upgrade. The second is to read your policy for a cosmetic damage exclusion, which some insurers attach to the same discount.
What "Class 4" actually tests
Class 4 comes from UL 2218, a standard for the impact resistance of roof coverings. IBHS describes it this way: steel balls of varying sizes are dropped from heights meant to simulate the energy of falling hailstones, and Class 4 means the product was still functional after being struck twice in the same spot by a 2-inch steel ball (2025 FORTIFIED Home Standard). UL says its test does not evaluate weathering or aging, and that there is "no currently established direct correlation" between steel balls and real hailstones (UL Standards). Rigid roofs such as concrete and clay tile are tested under a different standard, FM 4473, which uses ice balls; a Class 4 rating there also means two 2-inch impacts in the same spot.
Three things follow. A Class 4 label means the covering stayed functional in a lab test. It does not mean hail cannot dent, crack or wear it. It is a rating for the product, so installation, deck and age still matter. And it is not the only hail standard in use.
The newer IBHS hail ratings
IBHS developed its own test for asphalt shingles that uses lab-made hailstones fired from a pressurized cannon, and it scores damage instead of passing or failing. In its November 2025 scorecard, of 23 impact-resistant asphalt shingle products tested, none rated "Excellent," 18 rated "Good" and 5 rated "Marginal" (IBHS hail ratings). Under the 2025 FORTIFIED Home Standard, asphalt shingles must be rated Good or Excellent by IBHS to qualify for the Hail Supplement; a UL 2218 Class 4 rating alone no longer qualifies a shingle (FORTIFIED 2025 Summary of Changes). IBHS says Good and Excellent shingles outperform typical Class 4 shingles against realistic hailstones. Many insurer discounts are still written around Class 4 labels, so ask which standard yours accepts. See The FORTIFIED Home standard and insurance discounts.
What roofs qualify
| Roof covering | Typical hail rating route | Watch for |
|---|---|---|
| Impact-resistant asphalt shingles | UL 2218 Class 4, or an IBHS Good or Excellent rating | Ask the insurer which standard it accepts; the labels differ |
| Metal panels | UL 2218 Class 4 | Metal can resist functional damage but dent; see metal roofs and insurance |
| Concrete or clay tile | FM 4473 Class 4 (the route the FORTIFIED hail supplement uses) | Cracked tiles from foot traffic and hail |
| Low-slope (flat) roofing | FM 4470 Class 1-SH or 1-VSH, or UL 2218 Class 4 (FORTIFIED hail supplement) | Different standards apply to flat roofs |
Not every product marketed as hail-resistant carries a class. The carton, the data sheet or the installer's certificate states it, and if you cannot document the class, the insurer may not give the credit.
How the discount works
Who sets it. In Texas, the state Department of Insurance classifies roofing products Class 1 through 4 by impact testing and says that a Class 4 covering would receive the highest premium credit, but "the amount of discount for each class of roofing material is established by the insurance company on a company-by-company basis" (page dated February 24, 2023, read October 10, 2026). TDI also notes that the Texas Windstorm Insurance Association gives credits for labeled UL 2218 coverings, with the installer completing TDI Form PC068 (TDI). See Texas.
Which part of the premium. Credits usually apply to the wind and hail portion of the premium or the whole homeowners premium, depending on the filing. A percentage on the wind/hail portion will be smaller in dollars than the same percentage on the whole.
State rules vary and are changing.
- Minnesota requires a premium discount for homes with a FORTIFIED designation that includes the hail supplement (Minn. Stat. 65A.298), a stricter test than "Class 4 shingles." See Minnesota.
- Oklahoma's Strengthen Oklahoma Homes grants require FORTIFIED Roof with the Hail Supplement, and the state says insurer discounts are voluntary and set by each carrier (OID). See Oklahoma.
- Colorado enacted SB26-155 in June 2026, creating the Strengthen Colorado Homes Enterprise to fund resilient-roof retrofit grants from a fee on insurers. Beginning no sooner than January 1, 2027, and after the commissioner adopts rules, insurers will have to report each year how many homes have a resilient roof, what discount they applied, and their wind and hail claim results for homes with and without one. The bill reports on discounts, not a fixed credit, and the board is to define "resilient roof system" (SB26-155). See Colorado.
Most states have no verified rule requiring a Class 4 credit. Check home insurance rules by state and ask your agent.
The catch: cosmetic damage exclusions
Insurers that give a Class 4 credit sometimes attach a cosmetic damage exclusion to the policy, which removes coverage for dents, pitting and surface marking that do not stop the roof from working. The logic is that a roof rated to survive hail is expected to survive it, and the insurer does not want to pay for dents. The wording matters: "functional damage" defines what is still covered, and arguments about it are common after a hailstorm, especially on metal. Look in the declarations page's list of endorsements and the endorsement text itself. hail damage claims: roofs, siding and windows explains how these claims go, and the cosmetic damage exclusion entry has the definition.
Check the roof settlement terms too. A discounted roof can still sit under an ACV roof endorsement or a payment schedule, and those shift depreciation to you (Roof payment schedules and ACV roof endorsements). A discount that comes bundled with an ACV endorsement may cost you more on the first storm than it saved in a decade of premiums.
A hypothetical payback
Say your homeowners premium is $4,000 and your insurer's credit for a Class 4 roof is 15% of the whole premium, or $600 a year. A Class 4 shingle costs $2,500 more than standard shingles on your roof. The simple payback is about four years and two months, and it is faster if you are replacing the roof anyway. If the credit applies only to a $1,500 wind/hail portion, the same 15% is $225 a year and the payback stretches to eleven years. If it comes with a cosmetic exclusion and you live in a place where hail often dents roofs, the math may not work at all. These numbers are invented to show the arithmetic. Run your own through the roof and mitigation upgrade payback calculator.
Wind and hail is the most frequent homeowners claim: the Insurance Information Institute, using ISO data for 2019 through 2023, puts it at 2.80 claims per 100 insured house-years, with an average payment of $14,747 (III). Some of the value of the upgrade is a smaller chance of using your wind/hail deductible, not only the premium credit; see wind and hail deductibles explained.
How to get the credit
- Ask before you buy. Request the insurer's credit for impact-resistant roofing in writing, which classes qualify, what proof it needs and whether it comes with a cosmetic exclusion.
- Choose the product by its test label and keep the carton label, data sheet and any manufacturer certificate.
- Keep the paperwork: the invoice naming the product, the installer's certification (in Texas, TDI Form PC068 for the windstorm association's credit), the permit, and photos of the finished roof.
- Send it to your agent and ask for a re-rate, then check the premium notice for the credit line.
- Read the endorsements that arrive with the renewal.
Key takeaways
- Class 4 is a product test result from UL 2218 (steel balls) or FM 4473 (ice balls for rigid roofs). It shows a covering stayed functional under lab impacts, not that hail cannot damage it.
- IBHS now rates asphalt shingles on realistic hailstones, and none of 23 products earned "Excellent" in November 2025; the FORTIFIED hail supplement for shingles no longer accepts Class 4 alone.
- Credits are generally set by each insurer, vary widely and are tied to your policy's wording. Texas says so explicitly, Minnesota requires a discount only for FORTIFIED with the hail supplement, and Colorado's new law starts a reporting duty in 2027.
- A cosmetic damage exclusion or an ACV roof endorsement can cancel out the saving, so get both the credit and the endorsements in writing first.