Test-square hail-hit reference

The common industry benchmark is roughly 8 to 10 functional-damage hits within a single 10x10 test square, above which a slope is generally deemed replaceable rather than repairable. The exact number varies by carrier guideline, shingle manufacturer, and HAAG protocol, so confirm which threshold applies to your claim. This calculator lets you set the threshold and returns a meets-or-below verdict, so the count on the file is checked against the right standard.

You chalk off a 10-foot by 10-foot square — 100 square feet, one roofing square — on a representative area of each slope, then count the functional hail damage inside it. Testing a defined, repeatable area on every slope makes the inspection consistent and defensible: another adjuster can re-mark the same square and count the same way. Photograph each marked square so the count is tied to the field evidence when you write the roof scope.

Functional damage is a hit that shortens the shingle's service life — a bruise where the mat is fractured under the granule loss, a soft spot that gives when pressed, or exposed or displaced mat. It is not the same as cosmetic granule scuffing, blistering, or mechanical marks from foot traffic. Only functional hits count toward the test-square threshold. Marking and photographing each qualifying hit inside the square keeps the damage assessment defensible.

Standard practice is one test square per slope, placed on a representative area, so each direction of the roof is documented independently — wind-driven hail often strikes some slopes harder than others. Larger or complex roofs may warrant additional squares. Record the count and a photo for every square. This calculator evaluates one square at a time, so run it per slope and keep each result on the file.