Impact-Resistant (Class 4) Shingles in Minnesota: What the Rating Means and What Insurers Do

Class 4 is the highest impact rating a shingle can get under the UL 2218 test, and it can help a roof stand up to hail. It does not make a roof hail-proof, and in Minnesota it does not by itself earn you a state-required insurance discount. Here is what to know before you pay extra for it.

What the rating means

UL 2218 is a lab test. Steel balls are dropped onto a roofing sample to copy hail. Shingles are sorted into four classes, from Class 1 to Class 4. Class 4 takes the biggest hit and is the toughest.

A passing grade in a lab is useful, but it is not a promise. Real hail comes with wind. Stones can be bigger than the test ball. Read the warranty, and ask whether it covers hail damage. Many shingle warranties do not.

Which shingles are Class 4

Class 4 is a feature of specific products, not whole brands. A standard shingle from a maker that also sells a Class 4 line is not automatically Class 4. Here is what we confirmed on the makers' own pages and data sheets:

• Malarkey Vista. The current Vista technical data sheet lists UL 2218 Class 4 and describes the shingle as built with NEX polymer-modified asphalt.
• CertainTeed Landmark ClimateFlex. The CertainTeed product page lists UL 2218 Class 4 impact resistance. The regular Landmark is a different product.
• Owens Corning Duration FLEX and Duration STORM. Trade coverage of the launch says both carry the UL 2218 Class 4 rating. Standard Duration is a different product.

We could not confirm a Class 4 listing for the standard GAF Timberline HDZ, so we do not claim one. If you want Class 4, tell us at the inspection, and we will price the Class 4 option that fits your roof and your budget. Not every product is stocked in every color, so ask us what we can quote.

What Minnesota law says about discounts

Many homeowners hear that Class 4 shingles cut insurance bills by 20 or 25 percent. Those numbers come from roofers' sales pages. We did not find a Minnesota rule that sets them.

Here is what the law does say. Minnesota Statute 65A.298 requires insurers to offer a premium discount or rate reduction to owners whose homes meet the IBHS FORTIFIED program standards, which include a hail supplement. Owners must submit an IBHS certificate to get it. The discount applies only to policies that include wind coverage. The statute also lets insurers offer more generous credits on their own.

That tells us three things:

1. The state-required discount is tied to a FORTIFIED certificate, not to a shingle rating alone.
2. Some insurers may offer their own credit for a Class 4 roof. The statute allows it, but we cannot tell you which ones do.
3. The discount is whatever the insurer files and the state approves. It is not a fixed number.

The only way to know is to ask your agent. Ask these questions before you buy:

• Do you give a credit for a Class 4 (UL 2218) roof?
• What paperwork do you need?
• Does the credit start at renewal?
• Does my policy have a cosmetic damage exclusion or a separate hail deductible?

Hail in central Minnesota

The Minnesota State Climatology Office says that in a typical year hail falls somewhere in the state on 40 or more days. About 30 to 35 of those days have hail an inch across. Hail two inches or bigger shows up on about 7 to 8 days a year. Most hail is small. A few storms are not. In July 2024 a hailstone in Stevens County measured about six inches and may be the largest on record for the state.

Those numbers cover the whole state, not Crosby or Brainerd on any given year. But a roof in lake country is there for 25 years or more, and that is a long time to sit under the sky.

Is it worth the extra cost?

It depends on your roof and your risk.

• Worth a hard look: a full replacement you plan to keep 20 years or more, a lake home with a high-value roof, or a house that has been hit by hail before.
• Maybe not: a roof you plan to sell in a few years, or a budget where the price gap would delay the project.

Class 4 shingles cost more than standard ones. A typical replacement runs $9,000 to $22,000 installed, and we will show you the exact price difference on a written estimate. For a different kind of hail answer, see our standing seam metal options.

Bottom line

Class 4 helps a shingle resist hail, but it is not hail-proof. Minnesota's required insurance discount is tied to the FORTIFIED program, not to Class 4 alone. Call your agent before you decide, and get the discount in writing.

We will look at your roof and walk through the options at no charge. Book a free inspection.