How to tell hail damage from normal roof wear

Last reviewed 2026-08-11 · How we research and update this · How this site is funded

The signature of a hail hit

Hail damage is not one thing you look for. It is a combination of five features that appear together, and the combination is what distinguishes it from the half-dozen other things that make a roof look bad.

Random and non-directional placement. Real impacts have no order. They do not line up with the courses, they do not follow the nailing pattern, and they do not cluster along a path. If the marks are evenly spaced or run in lines, something manufactured or man-made caused them.
Circular impacts of similar size. Stones from one storm cell fall in a fairly narrow size band, so hits on a slope tend to be round and roughly consistent in diameter. Wildly mixed sizes and shapes point at debris, foot traffic or defects.
A dark bruise where granules are gone. Strip the granules off a spot and you expose the asphalt beneath, which reads as a black or very dark circle against the surrounding color.
Soft, springy feel under the thumb. The bruise is the visible half; the fracture in the fiberglass mat underneath is the half that matters.
Fresh, sharp-edged granule loss with shiny asphalt. Newly exposed asphalt still has its sheen. Within months it dulls and oxidizes to gray, and the edges of the scar soften as adjacent granules loosen.

You will sometimes also see short fractures radiating outward from the impact point, most visibly on 3-tab shingles and on the single-layer portion of a laminate. On very old shingles the mat can fracture completely and the hole goes through.

The bruise and the thumb test

A bruise is a fractured mat under an intact-looking surface, and pressing it is how you find it. Put a thumb on the dark spot with moderate pressure. Undamaged shingle is firm and does not move. A bruised shingle gives slightly and feels soft, springy or slightly hollow — the standard description is that it feels like pressing a fresh apple. Some inspectors find the fracture by feel before they can see the discoloration at all, particularly on multi-tone laminate shingles where the color blend hides a scar.

Do this in shadow or with the sun low if you can. Flat midday light washes out the contrast between exposed asphalt and granule surface; raking light throws each impact into relief.

Do not walk a roof to do this

Thumb-testing requires being on the roof. Steep pitch, wet or frosted shingles, tile, slate and any roof over one story are jobs for someone with fall protection and insurance. On a hot day you can also cause the very damage you are looking for, because hot asphalt scuffs and bruises under a boot.

What wear and manufacturing defects look like

Most of what homeowners photograph after a storm turns out to be one of these. Each has a giveaway.

Uniform granule loss along a whole slope. Granules shed steadily for the life of a roof, fastest in the first months after installation and then again as the asphalt oxidizes. Wear-driven loss is broad and even, heaviest on the sun-exposed slope and in the runoff paths below valleys. Hail loss is discrete: individual spots, with untouched surface between them. See granule loss for how to read the gutter.

Blistering. Gas or trapped moisture inside the shingle expands and raises a small bubble; when it pops it leaves a crater with granules gone. It looks remarkably like an impact. The differences: a blister has a raised rim or a visibly popped dome, there is no fracture and no soft feel underneath, and blisters usually appear on every slope regardless of orientation, because the cause is inside the shingle rather than outside it.

Cracking and crazing. Fine networks of surface cracks, often in a repeating pattern across many shingles, are the coating failing as it loses flexibility. Craze patterns are consistent shingle to shingle. Hail fractures are not.

Thermal splitting. Straight splits, frequently running vertically through several courses in a line, caused by expansion and contraction pulling the shingle against its fasteners. Their straightness and their alignment across courses is the tell.

Cupping and curling. Edges lift and corners turn up as the shingle dries and shrinks. This is an age and ventilation problem, and a roof that is curling badly is close to the end of its life whatever the weather did.

Nail pops. A fastener backs out and tents the shingle above it, sometimes wearing a hole through it. Nail pops sit exactly where nails go — in a line, at consistent spacing off the course line.

Foot traffic. Scuffed granules and bruised shingles concentrated in a walk path: from the ladder point, along the eave, up to the chimney, the furnace flue, the satellite dish or the swamp cooler. Damage that traces a route from A to B is not weather.

Algae streaking. Dark vertical streaks, usually on north-facing slopes, are Gloeocapsa magma. Cosmetic, biological, and not a claim.

Mechanical damage under branches. Scrapes, gouges, moss and abraded granules directly beneath an overhanging limb, arranged in the arc the branch sweeps in the wind.

Side by side: hail vs wear

Feature	Hail	Wear or defect
Pattern	Random, no alignment with courses or nails	Repeating, aligned, or following a path
Distribution across slopes	Concentrated on windward slopes	Even on all slopes, or heaviest on the sunny slope
Shape	Round, similar diameter within a slope	Craters with rims, straight splits, lifted edges
Feel under thumb	Soft, springy — fractured mat	Firm; no give
Exposed asphalt	Dark, shiny, sharp-edged if recent	Dull gray, soft edges, weathered
Soft metals nearby	Dented in the same storm	Undamaged
Timing	Traceable to a dated storm	Appears gradually with no event

Directional bias and which slopes to check

Hail does not fall straight down. It falls into a wind field, so stones arrive at an angle and strike the slopes facing the storm's approach far harder than the sheltered ones. On a typical hip roof after a real hail event you find heavy damage on one or two slopes, light damage on an adjacent slope, and effectively nothing on the leeward side. That gradient is one of the strongest pieces of evidence available, because nothing else on a roof produces it.

The corollary is uncomfortable but useful: a roof with even damage on all four slopes is more likely worn than hailed. If the marks are identical north, south, east and west, look harder at blistering, craze cracking and age. The exception is a very large or very long-duration event, or multiple storms from different directions over several years, which is exactly why the storm timeline for your address matters.

Before you spend money on an inspection, check whether hail even reached you. The hail history lookup lists every radar-detected hail signature near your ZIP with dates and estimated sizes, and the methodology page explains how those signatures are derived and what their limits are. If nothing of consequence has passed over your address in years, your roof is telling you about its age.

Soft-metal corroboration

Shingles are ambiguous. Soft metal is not. Aluminum and thin steel dent at impact energies well below what fractures a shingle mat, and they do not blister, craze or curl. If a storm was large enough to bruise your roof, it left a record on the metal around your house — and if the metal is clean, that is a strong argument that the roof marks are something else.

Check, and photograph, all of these from the ground:

Air conditioner condenser fins — the single best witness surface. Fresh dents in the aluminum fin pack, usually worst on the side facing the storm.
Gutters and downspouts — dimples on the top face of the gutter and on the exposed side of the downspout.
Vent hoods, turbines, ridge vents and pipe boot caps — thin painted steel or aluminum that dents readily.
Window screens and screen frames — torn or pushed-in mesh, dented frames.
Mailbox, garage door panels, fascia wrap, grill lids, patio furniture.
Wood deck boards and railing caps — hail leaves shallow round pits with fresh, light-colored wood exposed.

Take these shots with something for scale — a coin or a tape measure in the frame — and date them. The adjuster photo checklist lists the specific images an adjuster expects and how to frame them.

How a test square is chalked and counted

A test square is the standard way inspectors turn a subjective look at a roof into a number. The method is simple and you should expect to see it done.

Worked example. The inspector picks a representative 10-foot by 10-foot area — one square, or 100 square feet — on each slope, usually in the middle of the field and away from the walk path, valleys and penetrations. The boundary is chalked. Every impact inside the square is marked with chalk or a crayon, one mark per hit, and the marks are counted. The count is recorded per slope along with the slope's compass orientation.

A south slope comes back with 11 marked impacts, the west slope with 7, the north slope with 1 and the east slope with 0. That pattern — heavy on two adjacent windward slopes, effectively nothing on the opposite side — is the shape of a real hail event, and the per-slope counts are what the carrier uses to decide which slopes it will pay for. See repair or replace after hail for what happens when only some slopes qualify.

Thresholds are conventions, not law

Many carriers and contractors work to a rule of thumb in the range of roughly 8 to 10 qualifying impacts within a 100-square-foot test square before a slope is considered functionally damaged, and the figure varies by carrier, by state and by policy. A written independent inspection typically runs in the low hundreds of dollars where it is not free. Both of those are planning ranges, not quotes — confirm the number your own carrier uses before you assume a count settles anything.

Ask for the chalked photographs. A report that names slopes, gives counts, and shows the chalk is worth far more in a claim than a page of loose close-ups, and it protects you if the carrier's adjuster counts differently.

Before you call anyone

Work in this order. Check the storm history for your address so you know whether there is an event to point at and what date it was. Walk the property and photograph the soft metals. Look in the gutters for a fresh flush of granules. Then decide whether the marks on the roof match the hail signature or the wear signature above.

If the sizes involved are borderline, what size hail actually damages a roof explains the bands where insurers and contractors genuinely disagree, and why radar-estimated size is a reason to look rather than proof of loss. If the damage is on metal and your carrier calls it cosmetic, read the cosmetic damage exclusion first. And if you want the underlying material behavior — why a bruise happens on one roof and not another — start at roofing materials and how they handle hail.

Common questions

What does a hail bruise feel like?

Press a thumb into the dark spot. A bruise gives slightly and feels soft or springy, like pressing a fresh apple, because the mat under the surface is fractured. Undamaged shingle feels firm and does not move.

Is granule loss on its own enough for a claim?

Rarely. Adjusters look for granule loss with a fractured mat underneath at a discrete impact point. Uniform granule loss across a whole slope with no bruising reads as age, not as a storm.

What is blistering and why does it get mistaken for hail?

Blisters are gas or moisture bubbles that form inside the shingle and pop, leaving a small crater with granules missing. They look like impacts but they have no fracture below and no soft feel, and they are usually scattered across every slope equally.

Why do adjusters care which direction the slope faces?

Hail falls with the wind, so a real storm concentrates damage on the slopes facing into it. Damage that is even on all four slopes is far more consistent with age or a manufacturing issue than with a single storm.

Can I inspect the roof myself?

Do the ground-level work yourself: gutters, downspouts, the air conditioner condenser, vent hoods, window screens, deck boards and the mailbox. Leave the roof surface to someone with fall protection, and never walk a wet, steep or tile roof.

How recent does the damage look?

Fresh hail damage exposes asphalt that is still dark and shiny, and granule loss has sharp edges. Old exposed asphalt weathers to a dull gray and the edges of the scar soften, which is one way inspectors date an impact.

Sources

Every factual claim on this page that comes from outside our own data is sourced below. Where a number is a model or a range rather than a measurement, it is labelled as one in the text.