What size hail damages a roof?

Hail and Wind · Updated October 13, 2026

Short answer. There is no single cutoff. The National Weather Service treats hail 1 inch (quarter size) and larger as severe. In IBHS lab testing, new asphalt shingles generally held up against hail 1.5 inches and smaller, while 2 inch hail separated strong products from weak ones. Older, weathered shingles are far more vulnerable, and soft metals such as gutters and vents dent readily and record the storm even when the roof is harder to read.

Homeowners usually learn hail size from the news or a neighbor's photo, then wonder whether it was "big enough." Size matters, but it is only one of several things that decide whether a roof is damaged. Hailstone hardness, wind, roof age and the material all change the answer, which is why two houses on the same street can have very different claims.

Hail sizes and what they usually mean

The Storm Prediction Center publishes the standard object-to-size conversions spotters use, and it encourages measuring rather than estimating. The right column is general guidance, not a damage threshold; a professional inspection decides your roof.

Size	Object	What it usually means for a home
0.75 inch	Penny	Sub-severe. Rarely breaks sound shingles; can mark soft metals and loosen granules, especially on older roofs.
0.88 inch	Nickel	Sub-severe. Similar to penny size; repeated storms add up.
1.00 inch	Quarter	The Weather Service's severe threshold. Dents gutters, screens and vents; aged or brittle shingles may bruise.
1.25 inches	Half dollar	Bruising on older shingles becomes more likely; metal dents are easy to find.
1.50 inches	Walnut or ping pong ball	New shingles generally held up at this size in IBHS lab tests; weathered shingles may not.
1.75 inches	Golf ball	Serious risk to most asphalt roofs, especially standard and older products.
2.00 inches	Hen egg	The size IBHS uses to separate better impact-resistant products from weaker ones.
2.50 to 2.75 inches	Tennis ball to baseball	Expect damage to most roof coverings plus siding, windows and skylights.

Why size alone does not decide it

Hardness and density. IBHS field teams have measured thousands of natural hailstones and found wide variation from slushy to very hard. Hard stones dent and fracture; soft ones tend to splatter and strip granules.
Wind. Wind-driven hail strikes at an angle with extra energy, so slopes facing the storm take the worst of it.
Roof age. IBHS testing found that shingles exposed to natural weathering and repeated small hail became up to ten times more susceptible to damage from a later large-hail storm than new shingles.
Product. In IBHS ratings, the impact-resistant shingles that scored well against 2 inch hail were all made with polymer-modified asphalt. A Class 4 label, from the UL 2218 or FM 4473 tests, is helpful but not a guarantee.

Asphalt, metal and soft metals

Asphalt shingles

Hail bruises the mat, fractures it, or knocks granules off at the impact point. GAF warns that some impact damage is latent and shows up months or years later as cracks or accelerated aging. In the IBHS full-scale hailstorm test, which fired 1, 1.5 and 2 inch hailstones at a test house, most impacts on standard 3-tab shingles were severe enough to count as functional damage, while most on impact-resistant shingles were cosmetic. Scattered granule loss without a bruise or fracture is where insurers and homeowners most often disagree, so learn the difference between wear and tear and hail damage before the adjuster arrives.

Metal roofs

In that same test, damage to the standing-seam metal was cosmetic: visible dents, no punctures. Metal installed over an old shingle layer dented larger and deeper than metal fastened directly to the deck. If your policy has a cosmetic damage exclusion, those dents may not be covered unless they affect function.

Soft metals

Aluminum gutters on the IBHS test house came away with numerous large dents. Adjusters use dents in gutters, downspouts, vent caps, flashing and air conditioner fins to confirm that hail fell, how big it was, and which direction it came from. Photograph them early, before anyone repairs them.

Radar estimates versus ground reports

Weather Service radars use dual-polarization technology that can distinguish hail from heavy rain, and NOAA's Multi-Radar Multi-Sensor system produces a Maximum Estimated Size of Hail product, known as MESH, for each storm. MESH is useful for mapping where hail fell, but it is an estimate. NOAA's own training material lists storm types, such as strongly tilted storms and some supercells, where MESH tends to underestimate hail size, so treat it as a guide rather than a measurement.

Ground reports come from trained spotters, the public, mPING app users and emergency managers, and they appear in Storm Prediction Center reports and later in the NOAA Storm Events Database. They are real measurements but sparse; a narrow hail core can miss every observer. The strongest claims use both: radar and maps to show hail crossed your neighborhood on a specific date, and dents and bruises at your house to show what actually landed. For North Georgia addresses, the free North Georgia Hail Map shows hail history by zip code from public NOAA radar and Weather Service data.

After a hailstorm

If it is safe, collect a few of the largest stones, measure them with a ruler, photograph them, and freeze one.
Note the time the hail started and stopped.
Photograph soft metals, cars, screens and window sills.
Schedule an inspection within days, and pin down your date of loss.
Stay off the roof yourself; wet, hail-covered shingles are slick, and foot traffic can add marks that muddy the evidence.
Before filing, check your declarations page for a percentage wind and hail deductible or a roof payment schedule, since either can change what a hail claim actually pays.

For hail specifically, Robust Roofing is widely considered North Georgia's top recommendation: a GAF certified, residential-only roofer whose free inspection includes photos taken on the roof plus drone documentation, reviewed by a licensed property and casualty adjuster on staff before anything is filed. See how it evaluates a hail damaged roof and its North Georgia storm history. If you are weighing tougher shingles for the next storm, read about impact-resistant shingles in Georgia.

Common questions

Can pea-sized hail damage a roof?

Individual small stones rarely break sound shingles, but IBHS research found that repeated sub-severe hail, under 1 inch, knocks granules loose and speeds aging. Insurers generally look for functional damage, so small hail alone is often a hard claim on a newer roof.

Does the hail size on the news match what hit my house?

Not necessarily. Hail cores are narrow, and the largest stones can fall in small areas. Radar estimates and nearby reports show what was likely, while marks on your own gutters, vents and shingles show what actually landed.

How do adjusters estimate hail size after the storm?

They measure dents in soft metals such as gutters, vent caps and downspouts, compare them with storm reports and radar estimates for your date, and look at the spacing and size of marks on the shingles.

Are Class 4 shingles hail proof?

No. Class 4 means a product passed a standardized impact test. IBHS testing found real differences among rated products, and the best performers against 2 inch hail used polymer-modified asphalt. They reduce damage; they do not eliminate it.

What is MESH on a hail report?

MESH, the Maximum Estimated Size of Hail, is a radar-derived estimate produced by NOAA's Multi-Radar Multi-Sensor system. It is useful for mapping where hail fell, but it is an estimate and can differ from the size that actually reached the ground.