Hail Damage Revisited
It is that time of year again when we have thunderstorms with hail. And, we are sometimes called in to evaluate damage to roof to determine whether or not it is hail damage. There are times when these evaluations are easier than others.
Hail damage is rather obvious. It exhibits granule loss AND a bruise or fracture in the shingle mat. Granule loss alone is NOT hail damage. That is, according to tests by Haag Engineering, granule loss does not reduce the service life of the shingles.
A fracture in the shingle mat is a crack or break in the shingle. The shingle mat is either cracked or it is not cracked. A bruise is a soft spot on the shingle due to a fracture in the shingle mat that is not visible. The bruise feels like a bruise in an apple. The shingle mat is either bruised or it is not bruised.
If an area of granule loss is accompanied by a fracture or a bruise, it is hail damage, unless of course the granule loss and/or the fracture exhibits features indicative of being formed by something other than hail – that is, it is intentional damage. The features of damage done intentionally to mimic hail damage are discussed elsewhere in this website.
Other shingle anomalies may appear to be hail damage to the untrained eye, but their features are rather obvious. These are also discussed elsewhere on this website.
Here are photographs of some classic hail damage.