How does roof age impact wind and hail damage to your home?

How does roof age impact wind and hail damage to your home?

February 10, 2017 3:04 pm Published by

Did you know that wind and hail are more likely to cause damage to your roof as it ages? In order to understand why, we need to take a look at how roof damage occurs when impacted by hail versus wind.

Roof damage from hail

roof-damage-from-hail

As shingles age they get stiffer making them more likely to crack when impacted by hail. Although that seems obvious, it still takes large hail, ping pong ball size and larger, to cause damage even to the oldest roofs. What is sometimes classified as “hail damage” can be extreme aging, or, on a newer roof, defective shingles, sometimes termed ‘manufacturer defect’. It takes a skilled inspector to correctly assess cause.

Roof damage from wind

roof damage from wind

Now back to wind. Again, as shingles age they stiffen, which in theory would make them less susceptible to wind damage. However, something else happens with the aging process that makes roofs more likely to fail in elevated winds: sealant degradation. Those shingles need to be securely attached to the roof or problems rapidly compound. Once they start to bend upwards the force is even greater and can lead to cracking, ripping, or complete detachment. Research studies, both computer models and field inspections after hurricanes have documented the clear increase in damage at a given wind speed as roofs age (see citations).

Can hail and wind cause damage to new roofs?

Roof damage can still occur with new roofs but it seems a little contrary to the examples above. Whether you have a new home or just had your roof replaced, a funny thing can happen just after you’ve had your roof replaced. In the next windstorm you may see shingles flapping or even ripped from the roof. This could be due to improper installation, and the risk is greatest in the few years after a roof has been installed. There are many ways to improperly install a roof, including not allowing for sufficient time at the necessary high temperatures for the sealant to properly affix the shingles to the roof cover.

roofers fixing roof damage

Make sure your roofers know their stuff! Otherwise, you may find yourself doubly cursed. Roof damage from hail can leave you unlucky twice as you repair wind damage from your new, but improperly installed, roof. Recommendations from friends, neighbors, or your insurance company can help you find the right group to work with.

[1] Journal of Building Engineering 2 (2015) 36-43
Condition-based updating of the fragility for roof covers under high winds
Alduse, Jung, Vanli

[2] IBHS Report
Surviving Nature’s Fury: Performance of Asphalt Shingle Roofs in the Real World
Liu, Pogorzelski, Masters, Tezak, Reinhold