What Is Hail Size and Roof Damage?
Reported hail sizes use common-object names — quarter (about one inch), golf ball (about one and three-quarter inches), hen egg (about two inches) — and damage risk rises steeply with size, because a stone's energy grows much faster than its diameter. Smaller stones tend to show first on soft metals: gutters, downspouts, vents, and flashing take dents before shingles show functional damage. Larger stones can bruise or fracture asphalt shingle mats, crack tiles, and break skylights, and aging or brittle materials are damaged by smaller stones than new ones. The Austin metro sees the full range: of the 698 hail events NOAA has recorded across the five-county area since 2010, 528 reported stones of one inch or larger, 161 at one and three-quarter inches or larger, and 84 at two inches or larger. What a given storm did to a given roof is a slope-by-slope inspection finding — size alone settles nothing, in either direction.
Important Distinction
Note: Hail size alone does not establish a covered loss — and it does not rule one out. Size is a first read on risk; whether a particular roof was actually damaged is an inspection finding, and whether damage is covered is determined by the policy's own terms.
Also Known As
These are the search terms and phrases that commonly refer to this topic, so you can find it however you describe it.
How Hail Size and Roof Damage Relates to Other Topics
Reported hailstone size is the first read on whether a storm was likely to cause roof damage: hail around quarter size can begin to bruise asphalt shingles, and larger stones make functional damage progressively more likely.
The damage these size thresholds predict on asphalt shingles is the hail bruise — a mat fracture beneath the granules — which is why larger reported hail makes a slope-by-slope bruise check more urgent.
When reported hail in a neighborhood reaches the sizes that typically damage shingles, a professional roof inspection is how a homeowner learns what actually happened on their own slopes.
Class 4 impact-rated shingles are designed to raise the hail size at which the mat fractures, which is why the same storm can bruise one roof and leave its impact-rated neighbor largely intact.
Skylights concentrate hail risk: golf-ball-size hail that a shingle field might tolerate can crack a skylight dome, so an inspection after large hail includes the skylights and their flashing.
Related To Hail Size and Roof Damage
The four UL 2218 classes correspond to steel balls from 1.25 to 2.00 inches in diameter, which is why hail size is the natural companion question to a roof's impact rating.
Reported hail size is a first read on what a storm likely did, but the repair-or-replace outcome is decided by the documented condition of each slope, never by the size number alone.
Questions about Hail Size and Roof Damage?
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