Wind and hail can cause significant damage to buildings, and especially those buildings with a flat roof. The majority of commercial buildings have flat roof systems and can all be constructed differently. The most common construction materials include multi-ply asphalt systems, single-ply membranes or metal panels. The role of a structural engineer when constructing a commercial building is to determine the best material to use to withstand the weather conditions most commonly seen in the area. Some of the most damaging weather comes from wind and hail, and here’s how those conditions impact a flat roof.

Vulnerable Areas of A Flat Roof

With a flat roofing system, the most vulnerable areas prone to wind damage are on the corners and around the edges of the roof. This is due to the uplift pressure of the wind, which can actually be much faster than the horizontal wind speed itself. The problem with these vulnerable areas is when the perimeter of the roof gets damaged, it can start peeling back and lift up. In worst case scenarios, the wind pressure can get under the roof and essentially blow it off of the building. However, these scenarios are very rare, since structural engineering professionals have strict codes and guidelines to follow to ensure it doesn’t happen.

Is Hail Damage Only Cosmetic?

The type of roof covering used on a flat roof makes a difference in whether hail damage is only cosmetic or can create larger issues. Hail as little as ½” in diameter can create dents in a metal roof. While most of this damage is cosmetic, the finish on the roof could be compromised, cause rust and shorten the lifespan of the roof. Single-ply roofs are more vulnerable to experiencing damage that’s more than cosmetic. It will still take hail of 1” in diameter or more to cause serious damage, but every structural engineer suggests inspecting the roof frequently and thoroughly to determine any vulnerabilities.

Frequent Roof Inspections Can Prevent Significant Damage

Any structural engineering company will highly recommend conducting roof inspections often. The age of the roof plays a big role in how vulnerable it is to wind or hail damage. Too many commercial properties make the mistake of not replacing their roof soon enough, since severe wind and hail events don’t happen every day. But with the unpredictability of the weather, it’s best to be prepared and have a structural engineering professional out to make a recommendation on how to protect the roof from damage.

BE Structural is a team of structural engineering professionals with many different levels of experience. We are experts in commercial construction, residential construction and even various non-traditional projects. We are always available to serve you whether you have a new construction project or just need a thorough inspection of your property. For the best expert advice from a qualified structural engineer, contact us today.