There are four main steps to specifying door hardware: (1) hang the door, (2) secure the door, (3) control the door and (4) protect the door. This guide will explain some of the key terms used in each of these four steps.
Hinges or pivots?
Typically hinges are used to hang the door. There are a few basic types. Five-knuckle or three-knuckle are common choices.
Continuous hinges run the entire length of the door and are often used on exterior doors.
Pivots are used to hang the door when the door is heavy, the design of the door/frame requires pivots or because of an aesthetic preference.
Mechanical locks: There are many types of mechanical locks: tubular, cylindrical, mortise, interconnected and deadbolt. Below are the pros and cons of each type.
Tubular: Tubular locks have a center spindle assembly that extends through the center of the lock body and latch, allowing for retraction of the latch when the lever or knob is rotated. While this type of lock is very common on interior doors and in residential applications, they are considered the least secure lock type.
Cylindrical: Sometimes called bored locks, cylindrical locks are sturdier and considered more secure than tubular locks. The latchbolt assembly interlocks with one side of the lock chassis, making it easier to install, replace and rekey. Cylindrical locks are also available in different formats that provide various levels of security, all of which use the same type of key. This allows like-keyed and master-keyed systems that use a wide variety of locks. Cylindrical locks are vulnerable to security threats that use force to break them in two pieces–known as lock snapping or cylinder snapping.
Mortise: Mortise locks are considered even more secure than cylindrical locks. They require a pocket—the mortise—to be cut into the door where the lock is fitted. The mortise assembly includes the following:
Mortise locks are stronger and heavier duty than cylindrical locks, making them ideal for use in hospitals and schools. They are heavy enough to support ornate and solid cast knobs and levers. Mortise locks also provide a wide variety of choices for function, trim, keying systems and finishes, allowing for architectural conformity with the design of the building or locks and door hardware already on site.
Interconnected: An interconnected lock is comprised of two locks that are connected together so operating the lever handle will retract both the latchbolt and deadbolt simultaneously. The latchset is either a cylindrical or tubular lock, and there is a deadbolt above. These locks are most commonly used on dwelling unit entrance doors in multifamily residential buildings.
Deadbolt: Deadbolts, also called deadlocks, are available with a single cylinder or a double cylinder. The single cylinder deadbolt operates by a key on the outside and a thumbturn on the inside. A double cylinder deadbolt requires a key for unlocking on both sides of the door, and cannot be used on doors that are required for egress, except in certain locations where key-operated locks are allowed by code. With the exception of residential dwelling units, deadbolts are typically not allowed to be used on a door with another lock or latch installed, as the egress code requirements mandate one motion to unlatch an egress door.
Electrified hardware: Fail safe or fail secure
Electrified hardware uses power to control the locking and unlocking of the door. Most electrified hardware is available in one of two functions: fail safe or fail secure. Fail safe and fail secure refers to the status of the secure side (key side, outside) of the door. Most electrified hardware allows free egress from the egress side (inside) of the door.
An electric strike replaces the regular strike for a lockset or panic hardware. It is used as part of an access control system to provide added security and convenience such as traffic control and remote release. An electric strike is typically paired with a storeroom function lockset or panic hardware, so access is controlled by the electric strike.
An electromechanical lock is a lockset that has been electrified so that it can be controlled by a card reader, remote release or other access control device. Most electromechanical locksets allow free egress at all times.
An electromagnetic lock is an electromagnet that mounts on the frame, with a steel armature mounted on the door. When power is applied to the magnet, it bonds to the armature, securing the door. Electromagnetic locks are only available fail safe. When you remove power, the electromagnetic lock unlocks.
An electronic lock is controlled by a reader, such as a keypad, card reader or biometric terminal. If the user has the right personal identification number (PIN), card or biometric, the door unlocks. There are two main types of electronic locks: standalone and networked.
Credentials are the tools that give you access. Although modern security systems use different types of credentials, a key is the most widely recognized. When they are lost, new ones must be duplicated and, frequently, locks must be rekeyed.
An exit device (also called a crash bar, panic bar, panic device, panic hardware or push bar) allows the exterior side of the door to be locked, while ensuring that people can always exit from the interior. Consisting of a spring-loaded metal bar or touchpad mechanism fixed horizontally to the inside of an outswinging door, it activates a mechanism which unlatches the door, allowing occupants to leave quickly when the lever is either pushed or depressed. Panic hardware is required for doors which lock or latch, serving assembly and educational occupancies with an occupant load of 50 people or more (100 people or more for some codes), and also for high hazard occupancies.
There are several types of exit devices:
And it has dogging?
Dogging is a feature used in exit devices to hold the touchpad or crossbar in a retracted position, thus allowing a door to operate in push/pull mode without latching. Mechanical dogging is not allowed for fire doors, so fire exit hardware will not have the ability to be mechanically dogged. Fire doors may be dogged electrically, as long as the latches project upon fire alarm to positively latch the door.
Door closers are aptly named
A door closer closes the door after it is opened manually, but it also controls the door to avoid slamming and to meet the requirements of the accessibility standards. There are both manual and electronic door closers. Choosing a door closer involves considering a variety of criteria. In addition to the closer’s performance in fire situations, other criteria may include resistance to opening forces (including heavy duty models for areas with high winds), control over the rate of closing, safety, durability, risk of vandalism and aesthetics. There are five basic types of door closers.
Automatic operators provide easy access
Low energy automatic operators are used where a “knowing act,” such as a push button, is used to automatically open the door. They are required by code to open the door slowly and with a limited amount of force. Therefore they do not require the safety sensors and rails required for full-powered operators like the operators seen on a grocery store entrance.
There are many types of products designed to protect the door from wear and tear, including protective plates, push plates and pulls, edge guards, stops, gasketing and thresholds, and other miscellaneous products. When strategically placed on the door, these items can reduce abuse and wear of the door.
Working with a specification consultant
Some architects like to specify hardware, but we’ve met many who find it tedious. Product numbers and codes change, and integrating the various hardware products has become increasingly complicated. Mistakes can be costly and often impact construction schedules if they’re discovered late.
Whether you write your own specs or work with an architectural consultant, knowing the jargon for door hardware will help ensure your next project is safe and secure.
Allegion has a team of more than 150 specification writers located around the world who would be happy to assist on your next project. Contact an Allegion specification writer, or check out the iDig Hardware blog for information and updates on door hardware codes.
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