Should You Be Selling Stronger Garage Doors?

© 2003 Door & Access Systems
Publish Date: Fall 2003
Author: Tom Wadsworth
Pages 48-56

Should You Be Selling Stronger Garage Doors?
Lessons from Tornado Alley

by Tom Wadsworth

Every garage door dealer should read this story. It could greatly affect your contribution to safer homes and buildings in your area. Not to mention your profitability.

But before we begin, here are three facts and three events you should know.

Three Facts

1. The strongest garage doors in the world will not withstand a direct hit by a severe tornado.
2. Stronger garage doors that meet or exceed the building code, however, can have a significant effect on protecting homes from many strong winds.
3. Your garage door supplier is likely ready to supply you with these stronger doors.

Three Events

Three historic U.S. wind events are having a significant effect on our industry.

1. Hurricane Andrew of August 23-26, 1992, caused damage of $20.2 billion. According to the Insurance Information Institute (III), Andrew was the world’s second costliest insurance loss since 1970. (The Sept. 11, 2001, terrorist attacks—at $20.3 billion in losses—slightly edged out Andrew for first place.) Andrew triggered a cascading parade of events that encouraged the building industry, including the garage door industry, to produce products that offer greater protection against high winds.

2. The May 3, 1999, F5 Killer Tornado that ripped through the Oklahoma City area had a similar effect. The intensity and damage of that historic storm inspired a year of analysis by the first-ever survey of a tornado event by a Building Performance Assessment Team. After the team’s report, the Federal Emergency Management Agency (FEMA) publicly encouraged America’s homeowners: “Retrofit your existing garage doors to improve their resistance against high winds -- especially double-wide garage doors.”

3. The Tornadoes of May 2003 have the potential to be the costliest in U.S. history, according to the Insurance Information Institute (III). In May 2003, a stunning record of 571 tornadoes struck the U.S., more than double the normal frequency. The focus on stronger garage doors is now turning from the nation’s coastlines to the nation’s interior.

Since you may be familiar with the effects of 1992’s Hurricane Andrew, we turn our attention to May 3, 1999, a date which may mark a turning point for the garage door industry. Hear the voices of the people close to ground zero of that historic storm.

“It’s like God had a huge lawnmower and mowed down everything in its path.”

That’s how Alan Cheshier described the damage left by the May 3, 1999, tornado. Cheshier owns Muirfield Homes, a custom home builder in Norman, Okla.

After that massive F5 twister, Cheshier inspected damaged homes and attended a seminar about the structural damage to buildings. Here’s what he learned: In almost every occurrence, he says, the damage began after the wind blew in the garage door.

Since that storm, Cheshier says he started using insulated garage doors with heavier-gauge steel. Prior to 1999, he says his standard door was a non-insulated steel door. Cheshier’s homes also now routinely include extra wind-resistant components such as anchor bolts on bottom plates and hurricane straps on rafters.

He Didn’t Know

This veteran homebuilder says he didn’t realize that garage doors came in different gauges of steel. “I never knew that,” admits Cheshier. “And I think most builders don’t know that. You see two prices, and you buy the cheaper one, but you don’t ask why it’s cheaper.”

But Cheshier adds that he just recently had a storm with “straight winds of 70-80 mph” that blew in three non-insulated garage doors that he inspected.

Cheshier’s customers respond favorably to his efforts to build stronger homes. “Primarily, they get a feeling of security,” he says. “Every now and then, they reject it, but not very often.”

“We think houses should be made stronger to withstand high winds.”

That company motto is proudly displayed on the Web site at A large homebuilder in Oklahoma City, Home Creations is owned by brothers Jalal and Mohammad Farzaneh. Building homes since 1981, both have master’s degrees in architecture from the University of Oklahoma.

The May 3 tornado changed the way they build homes. On May 4, like Alan Cheshier, the Farzaneh brothers surveyed the damage area.

“It looked like an atomic bomb leveled the area,” says Jalal. “There were no leaves on trees. Every structure was flattened.”

The monster storm destroyed hundreds of buildings and killed more than 40 people along a 68-mile path. The Farzanehs, inspired to improve their building practices, hired a consulting engineer to study the damage and determine why homes failed.

The engineer was Harold Conner, Oklahoma University Professor Emeritus of Construction Science, who has spent nearly 20 years inspecting buildings after structural failure. His studies include the Alfred P. Murrah Federal Building in Oklahoma City after the 1995 bombing and the World Trade Center in New York City after the 2001 terrorist attack.

Conner concluded that homes would have less damage if they were built with better wind protection, such as anchor bolts on bottom plates, tornado straps on rafters, and exterior wall bracing.

Safety Pays

“My brother and I looked at each other, and we decided it was worth it to spend a good $500 on each house to make them stronger against winds,” he says. They also decided not to charge for it. Since then, every home they build includes wind protection components.

Their benevolent gesture turned out to be a profitable venture.

“Since we started building stronger homes, our sales have gone through the roof,” says Jalal. ”We built 100 homes in 1999, but we’re building 500 homes this year.”

He says 50 to 70 percent of their sales increase is due to the safety features. “We are now the largest homebuilder in the state of Oklahoma,” he says proudly.

But Garage Doors?

Farzaneh, however, has not been aware of the role of the garage door in protecting a home from winds. He says he just recently learned about it from the Fortified Homes project through the University of Oklahoma.

“In the committee, I learned that it makes sense to look into stronger garage doors,” he says. ”We are looking to fortify the garage door to improve the resistance of the home to high winds.”

“Our Tahoe in the driveway ended up three houses down in somebody’s kitchen.”

So says Janis Marlar, office manager at Moore Overhead Door in Moore, Okla. In May 1999, she had recently moved to Oklahoma from Colorado. Scrambling for cover after the tornado warnings, she huddled her family in the laundry room of her house.

It was the only room left standing. The tornado swept away her house and three cars, depositing the Tahoe in a neighbor’s kitchen.

Marlar says Moore Overhead Door now sells a lot of double-sided insulated steel doors with a 24-gauge exterior and 25-gauge interior skin.

“We also put commercial-grade hardware on all our residential doors. It’s standard,” she says. “It makes the door sturdier.”

Moore Overhead Door also sells storm-ready doors that were developed for south Florida. But so far, they’ve sold only one of those doors. Marlar believes that more people would request the storm-ready doors if they knew about them.

“I certainly would,” she adds.

You could call him a professional tornado chaser.

While others were running for cover from the May 3 tornado, Charles A. Doswell III, Ph.D., was chasing the beast in his car, camera equipment readied at his side. As debris fell around his car, he stayed in careful but hot pursuit.

“I followed along respectfully behind it,” he recalls.

Doswell has been chasing storms for 30 years. Equipped with bachelor’s, master’s, and doctor’s degrees in meteorology, he’s now the Senior Research Scientist at CIMMS (Cooperative Institute for Mesoscale Meteorological Studies) at the University of Oklahoma in Norman. He previously worked for the National Severe Storms Laboratory, (NSSL) also in Norman.

“I’m here in Oklahoma because of the winds in this area,” he says. “I’ve spent my life’s work studying and chasing tornadoes.”

Lessons Learned

Doswell has published extensively on the effects of winds on structures. “Lessons Learned from the Damage Produced by the Tornadoes of 3 May 1999” is the title of one of his reports, published with NSSL’s Harold Brooks in the Weather and Forecasting journal. Keenly aware that nothing could withstand a direct hit from an F5 tornado, Doswell focused on damage in peripheral areas outside the tornado’s center.

Doswell’s report noted the pivotal role of the garage door in homes where major structural damage occurred. He noted that the ability of the door to withstand the wind “depended on the orientation of the garage to the tornadic winds.”

Over the years, Dr. Doswell says he’s witnessed a host of homes where the garage door was clearly the initiation point of damage. “The house was essentially undamaged, except for the garage door and the garage,” he says. “I’ve seen that scores of times.”

Doswell served as the main author of the April 2003 National Weather Service (NWS) handbook published by the U.S. Department of Commerce. In that recent report, Doswell writes again, “It has been found that garage doors are common weak points.”

Seeking the Weakest Link

“Any high wind event seeks out the weakest link it can find in a structure,” he tells Door & Access Systems.

“When the garage door gives way, the wind then pressurizes the garage. In response, the roof then often comes off, and the failure of the garage can propagate into the home itself. In such events, the house tends to ‘unzip’ from the initial failure point.”

“If the door faces the wind, it’s more vulnerable,” he adds. “If the wind is approaching from a different direction, then the door may not be that susceptible.”

A Win-Win Situation

Doswell is one of many experts trying to raise awareness of wind protection among homeowners and homebuilders.

“I’d like to see the overall level of construction improved,” he admits. “I believe we can achieve a win-win situation where the builder wins, the garage door dealer wins, and the homeowner wins.”

Would homeowners in high-wind areas be wise to seek stronger garage doors? “Absolutely,” he quickly replies. “There’s no doubt about that.”

He then adds, “I would argue that anyone in the United States has the potential to experience 70-80 mph winds. If you have a flimsy garage door, you have a potential problem.”

Doswell says, “When I build a new home, it will have all the extra enhancements I can afford. These enhancements are easier to deal with in new construction and the cost is spread over the life of the mortgage.”

Tim Marshall may have been the first to identify the critical role of the garage door.

For 25 years, Tim Marshall has been assessing the performance of housing after major tornado and hurricane events. A Professional Engineer (P.E.) with Haag Engineering of Dallas, Marshall also holds a master’s degree in meteorology and another master’s in civil engineering. He is one of 20 people on the government’s rapid response team, and he has lectured widely and published numerous articles on the subject of housing damage in windstorms.

In 1980, Marshall co-published his first report on the role of garage doors in high winds, after studying tornado damage in Grand Island, Neb. In that groundbreaking study, he found that 51 percent of the damage or destruction of homes started when the wind blew in the garage door.

The pattern of damage seems to be consistent. (1) High winds hit garage door. (2) Door is the first to give way. (3) Wind rushes into garage. (4) Garage roof blows out. (5) Home roof tears away, resulting in loss of home.

Marshall also identified the critical role of garage doors in his published articles on 1992’s Hurricane Andrew in Florida and Hurricane Iniki in Hawaii. More recently, he noted the role of garage doors in a co-published work on the famous March 2000 tornado that hit residential and downtown areas in Ft. Worth, Texas.

In that report, he says significant damage resulted after the wind compromised the garage door. This then led to “uplift of the roofs or pushing out of exterior walls. Homes with attached garages facing the wind sustained far greater damage than homes with attached garages facing away from the wind.”

What’s a Garage Door Dealer to Do?

Marshall suggests that the garage door industry promote “a design for ‘high wind’ areas in the country and give the homeowner and builder an option (realizing it would be a more expensive option) to have a ‘hardened’ garage door/frame.”

What are “high wind areas”? The answer may be found in the new International Residential Code, now in effect in many parts of the nation. The code indicates that garage doors should be designed for at least 90 mph wind speeds and even higher speeds in certain regions.

Meteorologist Chuck Doswell believes that 60-70 percent of all tornadoes produce winds of no more than 100 mph. “In strong and violent tornadoes, … as much as 90 percent of the affected area experiences winds on the order of 100 mph or less,” he says.

Doswell concludes that “a considerable amount of damage caused by tornadoes is preventable … and the resulting structures need not be tornado-proof fortresses that cost a fortune to build.” Thus, structural improvements to homes and stronger garage doors that meet or exceed the building code can significantly limit damage.

The Industry is Ready

Joe Hetzel, DASMA technical director, says our industry is prepared to meet the demand for stronger doors. Through a joint effort by some of the industry’s top door engineers, DASMA has also produced Wind Load Guides and standards for testing garage doors for resistance to strong winds (ANSI/DASMA 108) and flying debris (ANSI/DASMA 115).

Garage door manufacturers have been wind-testing doors for decades, although specialized testing accelerated after Hurricane Andrew and subsequent changes to the South Florida Building Code. As a result, manufacturers have a range of garage doors that are prepared for higher wind load requirements.

Besides the widespread availability of wind-resistant products, DASMA also rolled out a new Certified Performance label program in January 2003. The door’s wind load rating is the first number published on the new DASMA label.

For example, if a dealer seeks to install a 16x7 door to withstand wind speeds of 100 mph, the door must have a rating of +15.3 psf (pounds per square foot) and -17.0 psf, according to the DASMA Wind Load Guide for the 2000 International Residential Code.

In August 2003, the greater Kansas City area building officials informed DASMA that the KC area is now “enforcing requirements for garage door installations to meet 90 mph wind loads,” according to Stephen Thompson, chief codes administrator. Thompson says they are also requiring that doors “bear evidence from the manufacturer of the compliance.” The new label program will do that.

The “Builder Door”?

As Alan Cheshier admitted earlier, homebuilders often refuse to buy anything but the cheapest garage door available. However, cheaper doors can mean lower wind protection. As homeowners and builders grow more wind-conscious and more aware of the role of garage doors in protecting the home, this practice may change.

Hetzel says door dealers can take a leading role in contributing to safer homes and buildings in their area. He urges dealers to know their local building code requirements and provide products that meet or exceed the code. “Educate builders and homeowners of the increased value of stronger garage doors,” he adds.

As a side benefit, dealer profitability could see a welcome increase. Since profit margins are generally minimal on the so-called “builder doors,” dealers can realize healthier margins for sales of stronger doors. Since “new construction” sales are often a significant part of the sales of the typical dealer, this up-sell may have a significant effect on dealers’ profitability.

“I think this point can be a great marketing tool for garage door manufacturers,” observes Baxter Vieux, Ph.D., P.E., the Director of the Natural Hazards and Disaster Research Center at the University of Oklahoma. “If you can get builders to request stronger doors, it’s a win-win situation for everyone.”


­ Builders can provide better and safer homes for their customers.
­ Homeowners can sleep better, knowing their homes provide a better level of protection against high winds.
­ Dealers can install better and safer doors for their customers, plus yield a healthier level of profitability for their sales.
­ Over time, as homes experience less damage from wind, the insurance industry can minimize losses and control the rising cost of property insurance premiums.

To respond to this story, send an E-mail to or send a fax to the editor at 815-285-2543.

Caption: The May 3, 1999, tornado in Moore, Okla., left total devastation in its path. FEMA photo by Chuck Doswell. Reprinted with permission.

Caption: This photo caught the Cordell, Okla., tornado near the end of its life on May 22, 1981. Photo courtesy of NSSL.

Caption: Damage expert Tim Marshall took this photo after the 2000 Ft. Worth tornado and published it as an example of how significant damage to structures often begins after the wind blows in the garage door. Photo by Tim Marshall, P.E. Reprinted with permission.

Caption: Tornado Days: This chart indicates the number of days per year when tornadoes touch down within 25 miles of any location. Source: Harold Brooks, National Severe Storms Laboratory.