GDO: The Weakest Link in Home Security?

© 2003 Door & Access Systems
Publish Date: Spring 2003
Michael Portman and Tom Wadsworth
Pages 36-40

GDO: The Weakest Link in Home Security?
by Michael Portman and Tom Wadsworth

In less than 10 seconds, a criminal can open a closed garage door secured only with a garage door opener (GDO). So contend the makers of Gaplock, a new automated locking device for automated garage doors.

“The weakest link in home security today isn’t back doors or bay windows. It’s the automated garage door,” says Al Corbi, a security professional and panic room authority.

“A wire clothes hanger …” says Corbi, “That’s all criminals need to break into homes these days.” Corbi was featured on a special Oprah Winfrey Show on “Home Security” on Feb. 13. Oprah referred to Gaplock as “an electronic deadbolt on the garage.”

Cord Grabbing

How do criminals do it?

Standing outside the garage, the intruder slides a hooked end of a straightened coat hanger between the header and top section of the door. The intruder then hooks the emergency release lever, or cord attached to it, and disengages the garage door from the opener with a slight tug. From there, the garage door can be manually opened, yielding an easy passageway to a vulnerable home.

Media Attention

The new break-in technique is getting some attention from the media. On Dec. 3 in Las Vegas, KLAS-TV reported, “Police … say home invasions are up, and the easiest way for intruders to get into your home is through your garage.”

The story said criminals are “drilling a hole through your garage door and using a metal wire with a hook at the end to pull on the rope that triggers your garage door to open. It makes it even easier if your garage door has glass windows they can look through.”

In November 2002 issue of Security Products magazine, Bill Tullock, a 32-year police veteran and Las Vegas crime prevention specialist, was quoted, “Today’s thieves (are) armed with coat hangers and simply lean against whatever overhead doors they’ve targeted. Using a bent coat hanger, they reach up and over the garage door and latch onto the emergency pull cord.”

Tullock says he sprayed his garage door windows with Rustoleum Frosted Glass spray to prevent thieves from seeing the cord inside. He told us he encourages homeowners to cut off the T-handle or end-knot found on many emergency pull cords: “Remove anything they can grasp.”

The Genie Company, however, says they discourage altering the cord in any manner. “This will result in a major safety issue if the carriage needs to be used in an emergency,” says Bryan Hantke, senior director of marketing. “The cord must be accessible from the floor, and UL states that the cord can be no higher than six feet from the floor.”

Taking the Show on the Road

Rodney Shoemaker, president of Automated Security Technologies (AST) and the inventor of Gaplock, demonstrated the cord-grabbing technique at the October 2002 CODA (California Operator and Door Association) show. Held in San Diego, the show attracted about 350 people from the door industry.

At the demonstration, Shoemaker was able to grab the cord and open the door – with no windows – within three seconds, reports Ty Kehlenbeck, CODA president. Kehlenbeck, a garage door distributor in Mission Viejo, Calif., was impressed.

At the 2002 International Security Conference in Las Vegas, Gaplock held a Garage Door “Break-In” Contest. The winner broke into a garage door in five seconds, using only a coat hanger. The cord-grabbing technique is reportedly a favorite way for locksmiths to enter homes where the owner is locked out.

Plugging Security Holes

GDO manufacturers have a good track record for developing innovative solutions to security issues. “Back-driving,” prying open the garage door to drive the GDO motor backward, was identified as a security threat several years ago. In response, most openers now include internal locking mechanisms that prevent back-driving.

When “code grabbing” attracted the media’s attention in 1995, remote control manufacturers developed rolling code technology to thwart electronically sophisticated thieves. Now, cord grabbing (or perhaps, “release grabbing”) is building some momentum, and Gaplock is plugging this apparent security hole for automated garage doors.

How It Works

Gaplock is designed to work with a new or existing GDO and a rolling code remote control to automatically lock the garage door every time it closes and unlock it before it opens. Shoemaker says the product protects automated garage doors from release grabbing, code grabbing, and back-driving. Installed on the door track on either side of a sectional door, the device blocks the rollers from moving up the track until the opener controls unlock Gaplock.

A Big Problem?

To hear another perspective, we spoke to several GDO manufacturers about the new product and the cord-grabbing threat. Genie’s Bryan Hantke admits, “Gaplock is an interesting device that can increase the level of security.” He adds, however, “I am not aware that cord grabbing is a huge problem at this time.”

Dan Nixa, residential marketing manager for Chamberlain, agrees. “We understand there's been a couple instances of this (cord grabbing), but this is not, by any stretch of the imagination, something that has been happening on a regular basis.”

“The garage door is the most visible part of most homes,” he adds. “Standing in front of the door is an unlikely place for a thief. Typically, they want to go around back where they can’t be seen.”

The Angle of the Dangle

Hugo Francisco, director of engineering at Marantec America, says that cord grabbing is not as simple as it may seem, but he admits that it’s “a very real issue.”

Francisco observes that the criminal needs to pull down on the release cord, and that would be difficult to do with a wire hanger. “Since the top of the top section is about the same height as the cord, the intruder would need to pull downward.”

If homeowners are concerned about cord grabbing, Bryan Hantke says the trolley arm can be mounted at a 45-degree angle instead of a 90-degree angle, moving the carriage and release farther away from the door. “If the carriage is 16 to 20 inches away from the door,” he adds, “the release would be more difficult to reach and disengage.”

Some Presumptions

“The Gaplock scenario of releasing the operator cord relies on several factors,” says Steve Krawczyk, the general manager of Hörmann U.S. operations. He says the cord-grabbing threat presumes “an attached garage, a clear line of sight, enough light to see the locking or release mechanism, and room to maneuver the coat hanger.”

He adds that the criminal must also be able to push in the top section to gain a workable gap against the header. “Hörmann operators feature an integral lock specifically designed to prevent uplift of the door, and our doors have support struts that reduce the threat of push-in from wind or human forces,” he adds.

Nixa noted that Chamberlain’s anti-back-drive mechanism might also deter the push-in threat. “When you put the hanger in, you probably need to back-drive the door slightly,” explains Chamberlain’s Dan Nixa. “Our PosiLock system is fairly sensitive and may detect the push-in and drive the door back down.”

The Window Weakness

Judging from the comments from the GDO industry, it may be more accurate to say that garage door windows are the weakest link, not the garage door opener. “Windows, while attractive, can reduce security,” notes Krawczyk.

“Windows for Hörmann doors are all made from an impact resistant acrylic which reduces the chance of push-out or shattering. Our window frames are sealed to the glazing material and the door itself.” He adds that Hörmann windows are also available in a crystal material that allows light to enter but cannot be seen through.

What About UL?

Most of our GDO respondents expressed some concern about Gaplock’s effect on the GDO’s compliance with UL (Underwriters Laboratories) requirements. “If it’s wired in with the operator, it may need to be reviewed,” John Hupfauer, UL’s lead engineering associate, specializing in garage door openers. “It might affect the loads on the operator.”

To install Gaplock, AST’s Shoemaker says the installer removes the GDO cover and makes a plugged connection. He adds, however, that his product does not alter or modify any GDO components and does not place additional load on the GDO. “It’s a simple retrofit to any opener,” says distributor Kehlenbeck.

“Based on our understanding of UL 325, Gaplock does not nullify the GDO's compliance,” he says. Shoemaker intends to pursue UL listing of Gaplock as a GDO accessory.

The Wall-Mounted Difference

Wayne-Dalton’s new wall-mounted openers have no trolley rail and no release cord dangling down the center of the garage door. Yan Rodriguez, residential products manager, says the openers’ release cord is mounted to the side of the door and not within the view of anyone outside of the garage (see photo).

In addition, the release cord works only if the cord is pulled straight out of the unit. “Since the would-be intruder can only pull down (not sideways), the opener will not release at all,” says Rodriguez. “Gaplock will decrease intrusion vulnerability on trolley-style GDOs, but the feature is redundant if a Wayne-Dalton wall-mounted opener is used.”

Does Gaplock have merit? Krawczyk says he doesn’t know the product’s service over time or the quality of its construction. “However, assuming it does everything the manufacturer claims, then I can see the savvy dealer using it as an up-sell accessory.”

More information about Gaplock is online at

Michael Portman is a freelance writer in Hollywood, Calif.
Tom Wadsworth is the editor of Door & Access Systems.