"How big does hail have to be to damage a roof?" is the question every homeowner and roofer asks after a storm. Here's the plain answer -- by size, with what to look for and what to do next.
| Hail size | Common name | What it does to a roof |
|---|---|---|
| 0.25″ | Pea | Rarely functional damage; can loosen granules on aging shingles. |
| 0.75″ | Penny | Granule loss and bruising possible, especially on older roofs. |
| 1.0″ | Quarter | Functional damage threshold -- bruises, mat fractures begin. |
| 1.25-1.5″ | Half-dollar / ping-pong | Damage common; inspections frequently justify a claim. |
| 1.75-2.0″ | Golf ball / egg | Widespread damage; vents, gutters, and soft metals dented. |
| 2.5″+ | Tennis ball to softball | Severe -- full replacements common; structural and skylight damage. |
Guideline only. Roof age, shingle type, slope, and impact angle all change the outcome -- brittle or older roofs are damaged by smaller hail.
Check any U.S. address free against NOAA storm records -- every date hail was reported nearby and the largest size.
Check your address Open the hail mapThe practical threshold for functional damage to asphalt shingles is about 1 inch -- quarter-size. Below that, hail mostly knocks granules off aging shingles (cosmetic to early-functional). At 1 inch and above, hailstones start fracturing the shingle mat, which is what an adjuster looks for: soft bruises that give under a thumb, cracked mats, and exposed asphalt. By 1.5 inches damage is common enough that an inspection is almost always worth it, and at 2 inches and up -- egg to softball -- widespread damage and full roof replacements are the norm.
On its own, pea-size hail (about a quarter inch) rarely causes the kind of functional damage insurers pay for. It can accelerate granule loss on a roof that's already aging, but a brand-new roof usually shrugs it off. The risk curve climbs steeply once hail passes an inch -- which is why the same storm can leave one street fine and total the roofs a mile away where the stones were bigger. A hail map shows that gradient.
Hail damage isn't always visible from the ground, and walking a roof is dangerous. Confirm the storm first, then get a professional inspection.
Start with the date. If NOAA recorded 1 inch or larger hail at your address, a claim is usually worth pursuing -- but check your policy's deadline (often a year from the date of loss, varies by state and carrier) and whether it's replacement-cost or actual-cash-value. Document the date and any visible dents before you call. The free hail history by address lookup gives you the exact dates and sizes on record near your home, and the printable hail report turns it into a one-page PDF.
The size-to-damage gradient is also your targeting map. After a storm, the hail map shows where the 1.5″+ swath fell; an approved (free) SwathIQ account turns that swath into a door-knock list of every address inside it above your size threshold within your markets, ready to export to your CRM. Access is hand-reviewed -- you'll get your invite within 24-48h. See how SwathIQ compares to other hail tools.
Data & method: NOAA MRMS MESH radar + NOAA/NWS SPC storm reports. Radar-indicated and observation-based -- informational only, not insurance or engineering advice.