Speed has a significant impact the door’s useful life and repair costs. The slow speed of conventional doors invites collisions because impatient drivers often rush through the half-opened doorway and clip the bottom of a door that is not yet fully open.
These accidents often happen when cars are lined up waiting to access the doorway. The second car in line rushes to follow the preceding car, making contact with the descending door. This impulse leads to door damage and damage to the second driver’s car.
At 1524 mm (60 in.) per second or faster, a high-speed door is too quick for a vehicle to clip the bottom of the rising door. At facilities where a driver uses a keypad code and a security card for doorway access, the door is generally fully opened before the driver’s foot moves from brake pedal to the gas.
Though most high-speed parking garage doors have rigid slats, some facilities are using fabric panel doors. The fabric panel doors used at the GID Sovereign at Regent Square project are easy to repair if they get hit and knocked out of their tracks. Facility maintenance staff can often put the fabric doors back in service by simply opening and closing the door, which rethreads the door into its guides. There is no need to call the door repair company and there are no bent parts to replace.
Most importantly, neither the rigid panel nor the fabric styles of doors can be taken out of service from vehicle collisions. For a busy facility, an unavailable door opening is a significant inconvenience for tenants, customers, and employees. Along with door speed, the relatively lightweight panels and properly sized drives make these doors capable of delivering hundreds of high-speed cycles, month after month, without stress to the system.
Advancements in door control design mean maintenance crews no longer have to go up a ladder to make adjustments in door operation. Newer door controllers have pre-programmed menu options that allow parking garage maintenance crews to easily adjust door operation at floor level to match the specific needs of each location. The controller’s self-diagnostic capabilities help keep maintenance time to a minimum.
Advanced door controller technology and variable frequency drives on newer doors generate an energy-efficient speed curve for smooth motion, soft starting, and soft stopping. These controllers continuously monitor all door activity and cycles and have self-diagnostic capabilities to simplify troubleshooting.
Zemski points out high-speed rigid slat door parts wear better compared to traditional overhead doors.
“We had a project where within three years the rivets in the door slats were already wearing out because the door coiled around itself, causing repeated rubbing and door component wear,” he explains. “Even though this door was to a reserved area that had limited use each day, within a few years, the rivets were worn down resulting in the slats coming loose and jamming the door.”
High-speed overhead doors have a coiled track so as the door coils up, it is not rubbing against itself. This means a longer service and cycle life, in addition to smoother operation. This feature enables painted finishes to enhance the look of the door.
The door controller technology has led to advancements in safety. Pedestrians should not be using the vehicle doorway to access the garage, but that does not mean they will not. High-speed doors can have a light-emitting diode (LED) illumination system that alerts when the door is about to close. On most doors, a combination of photo eyes and a reversing edge reduce the risk of injury.
However, do these safety features negate the security provided by door’s speed? These safety features are relatively unknown and most people will not risk being crushed by a speeding heavy duty door panel.