There are a lot of elements to a commercial door.

It can be overwhelming to the new or inexperienced to the door industry. So, let's cover common commercial door basics and vocabulary:

Astragal: A strip of steel or wood, which covers or closes the gap between the edges of a pair of doors.

Anchor: A device used to attach a door frame to the surrounding structure or wall.

Backset: The distance from the edge of a door to the center of the hole drilled for a lockset or deadbolt.

Ball Bearing Hinge: A hinge with ball bearings between the hinge knuckles, to reduce friction.

Base Anchor: A piece of metal attached to base of a door frame, to secure frame to the floor.

Butt (Hinge): A type of hinge designed for mortising into the edge of a door and into the rabbet of a door frame.

Cased Opening: A steel frame with no stops.

Change Key: A key on the lowest level of a master keying system. Change keys are also referred to as day keys. Typically change keys are issued to personnel that require access to one or two areas in a facility.

Continuous Hinge: A hinge that extends the full length of a door. Also known as a piano hinge.

Cylinder: The cylindrical-shaped assembly containing the tumbler mechanism and the keyway, which can be actuated only by the correct keys.

Cylindrical Lock Prep: Cutout in a door for locksets.

Deadbolt: A heavy duty door lock that has no spring action but is operated by a key or a thumb turn.

Double Doors: A pair of doors that meet in the middle of the door frame when closed.

Door Closer: A mechanical device that closes a door, in general after someone opens it, or after it was automatically opened.

Dutch Door: A door divided into two parts horizontally, allowing one half to be shut and the other left open.

Electric Strike: An electrical device that permits releasing of the door from a remote control.

Exit Device: A door-locking device designed to grant instant exit by pressing on a cross bar that releases the locking bolt or latch.

Face (Frame): Exposed part of frame when viewed perpendicular to face of the door also referred to as trim.

Filler Plate: A blank plate used to fill mortised cutouts.

Fire Rated Door or Frame: The ability of a door or frames to provide an effective barrier against the passage of flames, smoke and toxic gases and / or to reduce the transmittance of radiated heat.

Flush Bolt: A door bolt mounted (flush) on the inside face or edge of a door. Most often used on the inactive door of a pair of doors.

Flush Door: A door without glass and/or louvers.

Hand: A term used to designate direction in which a door swings. e.g., right hand or left hand

Header: A horizontal frame piece at top of opening or top member of transom frame.

Hinge Jamb: A vertical piece of a door frame prepared for installation of hinges.

Jamb: A vertical piece of a door frame assembly, adjacent to wall.

Kick Plate: A protective plate applied on the lower rail of the door to prevent the door from being marred.

Knocked Down Frame: A door frame furnished in three parts for assembly in the field.

Laminated Glass: A type of glass that holds together when shattered.

Latch Bolt: A bevel-headed spring bolt that holds a door closed, and is usually operated by a knob or a lever handle

Latch Protector (Latch Guard): A piece of hardware (attached to door) that completely covers the latch area protecting the latch bolt from prying and shimming.

Lite: Preparation in a door for view window, vision and/or glazing including glass stop and glazing bead.

Lite Kit: A complete “door window” kit; includes frame used to hold glass in place, glass and glazing tape.

Louver: An opening in a door with a series of slats or blades to allow passage of air.

Master Key: A key that opens every one of a given set of locks.

Masterkey System: An arrangement of cylinders having individual key changes, which permits them all to be operated by one key, called a master key.

Mortise: A cavity made to receive a lock or other hardware.

Mortise Lock: A lock designed to be installed in a mortise rather than applied to the door’s surface.

Mortise Lock Prep: Cutout in the edge of a door for mortise lock.

Mullion: A fixed or movable post dividing an opening vertically.

Pocket Door: A door that is prepared to slide into a pocket built in the wall.

Push Plate: A plate applied to the lock stile of a door, to protect against soiling and wear.

Removable Mullion: A mullion which can be temporarily taken out of opening to allow the passage of large objects through the opening.

Rough Opening: The size of a wall opening into which frame is to be installed.

Self-Closing: When a door must close on it’s own, with the assistance of closing hardware. Properly installed door closers or spring hinges will make a door self-closing. Self-closing doors are required for fire rated openings.

Sidelite Frame: The same as a borrowed lite except that it is attached to door frame.

Silencer: A rubber part attached to the stop on a frame to cushion the closing of a door

Stile and Rail: A model of door using stiles and rails either mitered or butted— corner joints welded and ground smooth—panel interlocks with stiles and rails and is provided with core or stiffeners—panel may be flush with (flush panel door) or recessed (recessed panel door) from faces of stiles and rails.

Stop: The part of frame against which door closes.

Strike: A metal plate that is pierced to receive the bolt or latch of a lock, when projected.

Strike Jamb: A vertical piece of a door frame prepared for installation of lock strike.

Threshold: A strip fastened to the floor beneath a door, usually required to cover the joint where two types of floor material meet.

Transom Bar: The part of a transom frame which separates the door area portion from the transom area portion.

Transom Frame: A door frame having a panel, louver, sash or glass above door opening with or without transom bar.

Transom Panel: A panel installed in a frame above the door opening.

Vision Lite: A window inside of a door; frame inside of a door used to hold glass in place.