Once again, hurricane season is right around the corner. If you live in a coastal area or in a location know to be hurricane-prone, the shape of your roof could determine whether or not your home will be damaged in the event of a hurricane, tropical storm or other high wind weather event.
Dr. Rima Taher, PhD, is a civil engineer and researcher at the New Jersey Institute of Technology and special lecturer at the New Jersey School of Architecture who has studied and lectured extensively on roof design and construction materials in relation to hurricanes.
A Scholarly Look at Roof Design
In a recent paper entitled, “Design of Low-Rise Buildings for Extreme Wind Events,” Dr. Taher came up with several things you need to know about roofs and high winds:
- A home that has a square floor plan — or, even better, a hexagonal or octagonal floor plan — stands up best to heavy winds.
- Hip roofs that have four slopes and other roofs with multiple winds can withstand heavy winds better than gable roofs, which are more common because they are more inexpensive to build. The optimal roof slope was 30 degrees.
- The force of wind on roofs tends to be upward lifting forces, which is why roofs are often blown off a structure during heavy wind weather events. But the way roofs are connected to walls can determine how much force it can withstand before being taken off. For example, prior to 1993 — when Hurrican Andrew hit Florida — local building codes allowed for some roofs to be stapled on to buildings.
- Roof overhangs are prone to wind uplift forces that can cause a roof to fail. The most wind-resistant roofs have overhangs less than 20 inches in length.
While there’s probably not much you can do to protect your roof after it’s already built, these tips can help protect the new construction from the force of hurricanes and other high wind events.