By Robert Toy
Whether you’re installing a new security gate for a self-storage facility in development or replacing the gate at an existing site, it’s important to research and compare product types. Each has its advantages and disadvantages, and knowing these in advance can help make your decision easier. Here’s an overview of the gates on the market as well as their pros and cons.
Slide Gate
This is the most common gate type, but don’t assume it’s going to be best choice for your site. It uses a chain, belt or hydraulic pump connected to pinch rollers to pull the gate open, and any supplier should be able to install it. Limit devices connected to the operator sense when to stop the gate in the open or closed position.
Advantages
- Security: Since the gate is a solid barrier, it helps to prevent unauthorized access to the property.
- Convenience: The gate may display signage that advertises the facility, explains operation of the access system, or shares access hours and safety warnings.
- Cost: Slide gates generally cost less than some other types of gates.
- Size: Slide gates can close off a larger opening than any other gate type. Most others are restricted to a maximum of 20 feet for a single operator. A chain-driven slide gate can generally close off an opening of 35 to 40 feet, and a hydraulic/track operator has an essentially unlimited opening width.
Disadvantages
- Space: The gate needs somewhere to retract while opening.
- Speed: Because of safety regulations, slide gates are restricted to a max opening speed of one foot per second. That can take quite a while if you have a large opening. Dual gate operators in a main/secondary configuration can be used for extra-wide openings. This increases speed, but at the expense of having two gates and operators.
Barrier Arm
These gates are also common and usually paired with a manual or motorized slide gate. This gate uses a motor connected through a belt or chain drive to a lightweight (wood, fiberglass, etc.) arm that can be up to 20 feet long. The arm rises to allow vehicle passage, and then automatically closes once the vehicle is through.
Advantages
- Speed: This operator has the quickest reaction time. It typically takes only two or three seconds to open. This can be especially useful in a situation where the entrance has limited space for vehicles to line up, for example, just off a busy street.
- Cost: These operators are the least expensive.
- Maintenance: They generally require less maintenance than other types.
- Space: The operator has a small footprint and requires no horizontal space to retract.
- Battery backup: Some brands have a built-in battery-backup system.
Disadvantages
- Security: Since the barrier is only a small arm, the path into the facility isn’t secure and the operator only provides traffic control. Therefore, this type of operator is usually backed up by a slide gate that will close after hours.
- Vulnerability: Since the arm is made of a lightweight material, it can be susceptible to damage from vehicles. However, it can be replaced at a lower cost than a metal gate in the same situation.
Swing Gate
This gate operator is less common than the others. The motor is attached to a pivot arm, which is then attached to a hinged gate that swings open like a door.
Advantages
- Security: The gate is a solid barrier, improving security.
- Convenience: Like the slide gate, the swing gate may display signage.
- Space: The gate requires no horizontal space to retract, which can actually be an advantage and a disadvantage.
Disadvantages
- Space: The gate needs to swing back when it opens. For this reason, it’s most often used for one-way traffic only. If used for two-way traffic, the keypad on the side the gate swings toward will need to be placed an adequate distance away.
- Installation costs: The cost of the gate fabrication may be more expensive than that of a slide gate. This gate also requires a more elaborate safety-loop installation than others.
Vertical Pivot Gate
A vertical pivot gate uses a motor and belt system, and is attached to a counterweight spring system with the gate mounted on top. This allows the entire metal gate (up to 18 feet long) to open vertically.
Advantages
- Speed: It opens faster than a slide gate, but not quite as fast as a barrier-arm gate.
- Space: Since the gate opens vertically, it needs no space to retract.
- Convenience: Like some of the other types, this gate may display signage. Depending on the weight of the signage, however, it may require adjustment of the counterweight system.
- Battery backup: The gate runs on a 12-volt marine battery that’s constantly charged. That means it has a backup if the power goes out.
- Security: The gate is a solid barrier, which helps improve site security.
Disadvantages
- Size: This gate is the largest of all types. Installing it requires a large concrete pad. It also requires mechanical help to unload it from its shipping transport and move it into position.
- Cost: This gate is more expensive than other types.
Vertical Lift-and-Fold Gates
A vertical lift-and-fold gate (VFL) combines the operating principles of a barrier-arm gate with a lift gate. It’s made of pickets connected to the gate arms through pivot points. As the arms are raised, the pickets "fold" into a smaller space.
Advantages
- Speed: It opens almost as fast as a barrier-arm gate.
- Space: It requires only a small footprint.
- Battery backup: Like a pivot gate, the gate operator runs on a 12-volt battery that’s constantly charged.
- Security: The gate is a solid barrier, which helps improve site security.
Disadvantages
- Installation: A more elaborate installation process is required, including a reinforced concrete pad.
- Cost: This gate is more expensive than some other types.
Optional Items
There are some optional items that should also be considered for your gate. On some models, these may be standard equipment. The first is a radio remote control or “clicker,” which is handy when you drive your cart from the office into the facility.
The other is a battery backup. If this doesn’t come standard with your gate operator, strongly consider it. You also want to make sure the backup unit can open and close the gate with the usual input when the power is out, not just open the gate and hold it open. Of course, your access-control system will need to be backed up as well.
Safety Requirements
Mo matter which type you choose, these gates aren’t meant for foot traffic. You should provide a separate pedestrian gate. In some jurisdictions, it’s required by local code.
All gates require safety devices, for example safety loops and detectors. Universal Laboratories 325 guidelines may call for additional equipment, such as infrared beams or contact edges.
Some jurisdictions may require the installation of an emergency gate-opening device for fire personnel. The type of device varies, so check with your local fire department for instructions. This device generally must be able to function even if the power is disconnected.
Before purchasing a gate and gate operator for your new or existing facility, consider the pros and cons of each type. Determine the factors that are most important for your site, and then choose a security system that will best fit your needs.
Robert Toy is an engineer with PTI Security Systems, which offers access control, door alarms and other site-security products for self-storage. He has worked in the industry since joining Doug West & Associates in 1992. For more information, call 800.523.9504; visit www.ptisecurity.com.
