Major windstorms impose extremely high wind pressures on garage doors. If the doors cave in, the house blows up like a balloon and can burst at the seams that hold down roofs and walls.
In a major windstorm, such as a hurricane or a tornado, it's the windows and doors that usually hold a house together. “Once you breach the envelope, the air rushing in pressurizes the building just like blowing up a balloon,” explains Scott Schiff, civil engineering professor and director of Clemson University's Wind Load Test Facility. In the best case, intense wind pressures invading the home blow out the windows, equalizing the pressure before severe structural damage occurs, but more often, the roof or whole wall sections blow out. “The house literally explodes,” Schiff says.
The incidence of damage due to internal pressurization had a big effect on building codes in 1992 following Hurricane Andrew, and ushered in a new era for the window industry selling impact-resistant, laminated glass units. Since then, entry door manufactures have followed suit, offering product lines to meet new wind-loading standards based on AAMA 101/I.S. 2/A440 — the latest certification of exterior, side-hinged doors. But perhaps most important of all, sharp attention has been given to garage doors.
Because of their size, garage doors are highly susceptible to collapse, says Tim Reinhold, vice president of engineering at the Institute of Business and Home Safety (IBHS), a non-profit arm of the insur
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