From this article you will gather some input on standing seam metal roof hail damage.
The roof integrity is a constant concern for all the property owners and there is a popular myth that standing seam metal roof can be easily deteriorated by hail. To allay the fears Roof Experts state: metal roof will withstand hail. But if the house is located in an area where this nature phenomenon is very frequent, then strong hail might make dents on the aluminum or copper roof, as they are soft metals, easily prone to physical impact. Steel standing seam on the contrary will better withstand such weather.
What size should hailstones be in order to damage the pitched roof? It depends on many parameters. First of all, it makes sense to define what is considered damage to the roof. If the roof integrity is not disrupted and there is no reason to think that its service life has decreased, then such damage is not functional. It is especially true if the hail is 1 cm size, has oval shape and no pointed edges.
There might arise a question as to how to estimate the size of hailstones that a roof withstood? To do this accurately, you should look for dents in the metal. As said above, the dents are usually found with copper and aluminum roofs, so you should look for dents on aluminum parts of air conditioning systems, ventilation and heating equipment on the roof. Dent size are typically equal to 80% of average hailstones.
If there was a major hailstorm and the hail stones have sharp edges, this can result in development of micro-fracturing in fragile types of roofs, like shingles for example. The thing with the standing seam however is that it is installed on top of solid plywood covered with bitumen waterproof membrane. These layers diminish the hit force dramatically thus preventing the metal from breaking. So, there is little chance for the zinc coating to be cracked or trampled in the impact area. In this case we are therefore talking about cosmetic damage.
At the same time the hailstorm would bring massive damage to shingle roof and will require serious repairs.
