Unrecognized by most homeowners (and unfortunately the media as well) is the fact that the garage door is potentially the largest, weakest opening of a residential home’s exterior envelope to a hurricane. Many people that are concerned about the safety of their homes and families in hurricane conditions (even those that pay thousands of dollars for window shutters and impact resistant windows) fail to take any precautions to properly secure their garage door. The Florida Alliance for Safe Homes has stated that “about 80 percent of residential hurricane wind damage starts with wind entry through the garage door.” According to the Federal Emergency Management Agency (FEMA) and the American Red Cross in their booklet “Against the Wind – Protecting your Home from Hurricane Damage”, the loss of the garage door was one of the four major factors in homes destroyed or damaged in Hurricane Andrew. As the American Red Cross warns, once the garage door goes, the full power of a hurricane enters the home, blowing off the roof and resulting in major damage to, if not complete destruction of, the home.
The National Oceanographic and Atmospheric Administration took the photograph below after Hurricane Andrew. Note the six homes in the center of the photo. Of these, the four houses on the right lost their garage doors and also their roofs. The two on the left retained their garage doors. While these two homes experienced some damage to the roof tiles, their roofs and overall structures fared much better than those homes whose garage doors were lost.
Why is it so crucial to reinforce the garage door? Studies have shown that hurricane winds exert the greatest pressure and suction at the corners of a structure, which is the location of most garage doors. A garage door is held in place only by the door’s tracks. Hurricane winds exert both tremendous pressure and suction on the garage door, causing it to flex inward and outward. Consequently hurricanes generate severe stress not only on the door but on its supporting tracks as well. As the pressure builds, the garage door pushes against and pulls away from the garage door tracks. If either the tracks or door give way, the garage door blows in or is sucked out. This allows the full power of the hurricane force winds to enter the compromised structure and attack the roof and walls. Homeowners focus on securing the windows by applying shutters or installing expensive impact-resistant glass yet this weakest and most important area, the garage door, is often either ignored or inadequately protected, reducing the value of investment in shutters or impact-resistant windows. With the enormous number of attached garages in the coastal states, failure to properly safeguard this single largest area of vulnerability is a major weakness in overall storm readiness.
One stop-gap measure that some in the media have endorsed is to back an automobile up against the garage door. Anyone who believes that this is a viable approach for garage door protection should go to a test laboratory and see what hurricane force winds in excess of 100 mph do to a typical steel garage door. They will quickly realize that their car is wholly inadequate garage door reinforcement. Or simply look at the photo below in which the hurricane blew in the garage door despite the two cars inside, and then blew out the roof. Furthermore this tactic is completely worthless in protecting the garage door from the tremendous outward suction forces the garage door experiences in a hurricane, which are often even more powerful than the incoming winds.
So how do homeowners obtain the protection from hurricane winds needed for their garage doors? Hurricane resistant garage doors can be purchased but these doors are expensive and may require a building permit for installation. Many models of these doors are rated to provide protection against winds of only up to 120 mph, a wind speed that is exceeded hurricanes rated Category 3 and higher. Historically 40% of the hurricanes striking the U.S. have been Category 3 or stronger. Hurricane shutters for garage doors are expensive, can be cumbersome, and may also require a building permit. Retrofit systems employing horizontal bracing are available, but horizontal braces just strengthen the door and do not reinforce the garage door’s tracks, and thus have limited effectiveness. The September 1998 booklet published by the Institute for Business & Home Safety (in cooperation with FEMA, building officials and insurance companies) emphasizes vertical bracing for garage doors. This booklet, in its three and only illustrations on retrofitting a garage door, shows vertical braces not coincidentally similar to Secure Door’s patented product that attach to the header, garage floor and to each hinge or door shackle on the door.
Click here to see this booklet and note these illustrations of vertical braces on pages 12 and 13 of the booklet (file pages 18 and 19 of 36)..
Without an understanding of the importance of protecting garage doors in homes with attached garages, homeowners can gain a false sense of security from buying shutters alone. The average homeowner wouldn’t think of putting shutters on just two or three sides of the house, but a standard 7′ x 16′, 112 square foot, unprotected double garage door opening likely exceeds the window square footage on one or two sides of the average home. Homeowners concerned with properly protecting their homes from hurricane force winds should strongly consider Secure Door, the highly effective and very affordable hurricane protection solution.