The Hail Damage Roof Calculator answers the two questions homeowners have after a hailstorm. First, should the roof be inspected: it compares the largest hail you saw with the National Weather Service's 1-inch severe threshold and with the steel-ball size your shingles' UL 2218 impact class was tested against (1.25, 1.5, 1.75 and 2 inches for Classes 1 to 4). Second, what would an insurance claim actually pay: enter a repair or replacement estimate, a flat or percentage deductible, the roof's age and whether the policy settles at replacement cost or actual cash value, and it shows the deductible, the depreciation withheld, the first payment, the recoverable depreciation released after the work is done, and your own out-of-pocket cost.
Two numbers decide whether hail is a roof problem: the size of the stones, and the size your roofing was tested against. The National Weather Service treats hail of one inch — quarter size — and larger as severe. Under UL 2218, roofing earns an impact Class 1 to 4 by surviving steel balls of 1.25, 1.5, 1.75 and 2 inches without cracking.
| Hail size | Diameter | NWS severe? | UL 2218 classes tested at or above it |
|---|---|---|---|
| Pea | 0.25 in | No | Class 1, Class 2, Class 3, Class 4 |
| Mothball | 0.5 in | No | Class 1, Class 2, Class 3, Class 4 |
| Penny | 0.75 in | No | Class 1, Class 2, Class 3, Class 4 |
| Nickel | 0.875 in | No | Class 1, Class 2, Class 3, Class 4 |
| Quarter | 1 in | Yes | Class 1, Class 2, Class 3, Class 4 |
| Ping-pong ball | 1.5 in | Yes | Class 2, Class 3, Class 4 |
| Golf ball | 1.75 in | Yes | Class 3, Class 4 |
| Tennis ball | 2.5 in | Yes | Larger than every test ball |
| Baseball | 2.75 in | Yes | Larger than every test ball |
| Softball | 4 in | Yes | Larger than every test ball |
| Replacement cost (RCV) | Actual cash value (ACV) | |
|---|---|---|
| Depreciation | $8,000 | $8,000 |
| First payment | $10,000 | $10,000 |
| Paid after the work | $8,000 | $0 |
| Insurer pays in total | $18,000 | $10,000 |
| You pay | $2,000 | $10,000 |
Straight-line depreciation is an illustration; each insurer applies its own schedule, and some roof endorsements pay on a fixed table by age.
The National Weather Service treats hail of 1 inch (quarter size) and larger as severe, because damage rises sharply from that size. Smaller hail can still mark soft metals and older, brittle shingles, so a check after any hail is sensible.
Soft dark spots where granules have been knocked off, bruises that feel spongy under a finger, cracks or torn edges, and a heavy wash of granules in the gutters. Dents in gutters, downspouts and vent caps are the easiest evidence to photograph from the ground.
Under UL 2218 the product was struck twice in the same spot by a 2-inch steel ball without cracking. Classes 1, 2 and 3 use 1.25, 1.5 and 1.75-inch balls. It is a lab rating, not a guarantee against every storm.
Hail is normally a covered peril, but what you receive depends on the deductible and whether the roof is settled at replacement cost (RCV) or actual cash value (ACV). ACV deducts depreciation for the roof's age and never pays it back; RCV withholds it until the work is done.
Not when the repair costs less than the deductible — the insurer pays nothing and the claim may still be on your record. Wind and hail deductibles are often a percentage of dwelling coverage, which can be several thousand dollars. Run your own numbers first.