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The scope of this technical date sheet is to provide industry-accepted definitions for common rolling door terms, with a rolling door being defined as a vertically operating, coiling door typically used in commercial or industrial applications. The terminology information encompasses many common terms used in the rolling door industry.


Angle Mounted TrackA method of fastening vertical track to a doorjamb using a full height continuous angle.
AnodizeAn electrolytic method of coating aluminum with a protective or decorative film, which is generally clear in color.
AstragalA compressible or deform-able seal provided on the bottom edge of a door.


Back HangsThe vertical supports for the horizontal track, cross-braced to prevent lateral movement and track spread.
BackroomThe required clearance from the face of the header to any obstruction to the rear of the horizontal track.
BeadA metal, vinyl or rubber strip used to secure glass around the periphery of a pane.
Bottom BracketA structural support located on the bottom section of the door which provides for attachment of the lifting cables on the sectional doors. Also referred to as Bottom Corner Bracket. (Note: Track rollers may have a separate door attachment in some door designs.)
Bracket Mounted TrackA method of fastening vertical track to a doorjamb using angle brackets. Also referred to as Mounted or Track Bracket.
Break-Away TrackVertical track assembly that steps back from the jamb used for high lift and vertical lift track to permit outside lock handle projection to clear the lintel.
Bumpers SpringA leaf spring installed at the end of the horizontal track. Especially useful on lift clearance or full vertical manually operated doors, acting as a cushion and stop.
Base PlateOptional plate mounted on the floor to distribute weight from a framing system supporting the door.
BellmouthFlared upper portion of guides to ease entry of curtain into the guides.
Between Jamb MountedType of mounting where the guides are positioned between the mounting surfaces and not on the surface (interior or exterior) of the wall.
Bottom BarA reinforcing member at the bottom of a curtain or curtain panel.
BracketsPlates bolted to the wall or to extensions of the guide wall angles that serve to support the barrel and form end closures for the hood.


Cable Sensor EdgeAn edge that uses two cables inside a standard neoprene loop astragal. Upon connection with motor operator, a sensing field is established between the two cables. Any disturbance to this field causes the motor and door to stop and reverse (or stop).
Counter ShutterA door which closes on a counter-type sill.
CounterbalancingA method by which the hanging weight of the door curtain is balanced by the helical torsion springs or weights.
Crush PlatesBearing plates provided where doors are mounted on wall units with hollow cells to accommodate through-wall bolts to prevent crushing of the hollow wall.
CurtainInterlocked slats assembled together.
Curtain SlatsFormed or extruded members that comprise the curtain on a rolling door.
CycleAn action on the door from the fully closed position, to the fully open position, and returned to the fully closed position.
Cylinder LockKey-operated locking device located on the bottom-bar.
Chain HoistA mechanical device used to raise and lower the doors by use of hand chain.
ClearancesThe amount of side room, headroom, and backroom required to properly install a sectional door.


Door FrameThe frame into which the door fits, consisting of two upright members called doorjambs, and a door header.
Door SizeAlways specify the width first and the height second: For instance 8’ 6" (2591 mm) wide by 7’ 3" (2210 mm) high.
Drums CircularStamped metal parts attached at various locations along the tubular shaft that allows the sheet door curtain to coil up when the door is opened.
Door/Grille ComboCombined assembly of a rolling service door and a rolling grille sharing guides and common bracket plates. Allows full security when required and ventilation with door opened and grille closed.
Double Throw LockCenter locking device that throws a locking bar into both guides, mounted on bottom bar.
Drive GearLarge gear for chain- or crank- operated units. It is directly fastened to the door shaft on the drive side bracket plate.
Drive ShaftThe shaft in the barrel that is securely attached to the barrel, through welding or pinning. When this shaft rotates the barrel should also rotate.


"E" GuidesCommon expression for the shape that guides form when they are mounted to steel jamb supports or frames.
EndlockA component which is attached to slats to prevent lateral shifting.
Exterior HoodA hood mounted on the exterior (weather exposed) surface of a wall.
Exterior MountedCondition where door is mounted on the exterior (weather exposed) surface of a wall.


Face of WallDoor mounting condition where guides mount directly to the wall, and side clearance is allowed for tension wheel and drive mechanism.
FasciaMetal closure for the back of door housing.
Fenestrated SlatsA curtain with slots in slats to allow air infiltration.


GuideVertical assembly in which the curtain travels and that is fastened to the jamb, retaining the edges of the door curtain and closing the space between the curtain edges and the jamb.
Guide StandoutThe distance that face-mounted guide assembly extends from wall face.
GussetMetal reinforcement plate, angle or bracket which is fastened in corners to stiffen joints.


Hand of OperationThe side on which the door operator is placed, as viewed from the mounting-surface side of the door. It is either a right-hand (RH) or left-hand (LH) operation.
Header SealWeather-stripping mounted at opening header to seal the opening between header and curtain.
HeadroomVertical clear space required above the door opening, and bellow the lowest ceiling obstruction, required for proper installation and operation of the door and its hardware.
HelicalA term referring to the type of torsion spring used in the spring counterbalance.
High Cycle DesignDoor components and operator designed for a fixed number of cycles for a specific period of time.
HoodA housing that mounts horizontally, serving as an enclosure for the counterbalance.
Hood BaffleA flap of material with one end secured to the interior of the hood and the other end resting on the curtain, designed to retard air infiltration over the top of the curtain and through the hood.


Interlock, ExternalAn electro-mechanical device that prevents motor operation when door lock is engaged.


JambThe vertical member that frames the side of an opening in the wall.
Jamb LoadForce exerted on jamb by guide assembly when curtain is subjected to wind load.


Lift-HandleA handle attached to the inside or outside of a door section, to be grasped by hand when a door is to be operated manually.
LintelA horizontal member spanning and carrying the load above an opening.


Master KeyingArrangement whereby cylinder locks, although fitted with different keyed cylinders can be opened or locked by means of one "master" key.
Mounting PlatesFlat steel or wood members placed on the wall to accommodate spring support, spring shaft bearings, chain hoists and mountings for operators.
Movable Center PostA lightweight extruded aluminum post/track assembly, which substitutes for the jamb between two adjacent doors and can be released and carried from the opening.
MullionA slender dividing bar between two doors; usually designed to carry horizontal (wind) load but not vertical load.


OffsetDimension between face of header or jamb and center-line of curtain. Required to reduce drag of curtain on bell-mouth of guides when curtain is in a lowered position.


PackoutGuide built-out to clear an obstruction or provide clearance for drive or tension mechanism when door is between-jamb mounted.
Pass DoorHollow-metal pedestrian door integrated into the rolling door, the frame of which is hinged at the jamb so door-frame swings out of the opening.
Plug EndDrive end of barrel assembly driven by gear or sprocket for which the curtain is raised and lowered. Consists of assembly of short solid shaft and one or more sound plates welded to the shaft and pipe, which fit within the pipe.


Rolling Counter Fire DoorA fire rated door assembly with an automatic-releasing devised used in fire rated walls where the primary purpose of the opening is for non-pedestrian use, such as counter service for food, a pharmaceutical dispensary, package and baggage transfer.
Rolling DoorA vertically operating, coiling door typically used in commercial or industrial applications.
Rolling Fire DoorA fire rated vertically operating coiling door assembly with an automatic-releasing device typically used in commercial or industrial applications, providing protection in fire rated wall openings.
Rolling GrilleA vertically operating coiling door consisting of assembled interlinked rods of steel, stainless steel, or aluminum.
Rolling Service DoorA vertically operating, coiling door typically used in commercial or industrial applications, with a curtain consisting of formed metal slats interlocking together.


Security Chain BoxMetal enclosure that encloses hand chain in a steel pad-lockable assembly attached to door guide.
Sensing EdgeA device added to the underside of the bottom bar of a power operated rolling door, which stops or reverses the door curtain upon contact with an obstruction when closing under power.
Service Counter DoorAn assembly consisting of a rolling counter door that incorporates a four sided framed used in walls where the primary purpose of the openings is for non-pedestrian use, such as counter service for food, a pharmaceutical dispensary, package and baggage transfer, or observation ports.
SetbackA standard space where the guide is recessed from edge of the jamb at both sides of opening on a face of wall-mounted door.
SideroomRequired unobstructed space on either side of the opening.
Slide GrilleA side-sliding grille product that requires little headroom and no floor track. The grill is able to follow a curved lease line and stacks into a side pocket in the wall.
Sloped Bottom BarBottom bar with a vertical dimension larger on one end than the other, to match sloped sill opening. Requires additional head room to keep clear opening when door is up.
Stand-outThe distance that guide assembly extends out from the wall on face-of-wall mounted doors.
Starter SlatsPartial slats used to connect curtain to barrel or barrel rings.
Stopsbars mounted at top of guides to prevent bottom bar from traveling out of the guides when the curtain is fully raised.


Tension WheelA component attached to the counterbalance tension shaft, which controls the spring tension as it is locked to the bracket.
Thru-Wall OperationA door driven by means of a hand chain, crank or motor operator located on the opposite side of the wall.
Torsion SpringA spring that works by turning one end about a longitudinal axis while the other end is held or turned in the opposite direction, developing torque.
Tubular OperatorA cylindrical operator that mounts directly into the pipe and electrically drives the barrel assembly.


Vehicular Access DoorA door, typically a garage door or a rolling door, used primarily for vehicular access into a building.
Vertically Acting DoorA door that is typically a garage door or a rolling door.
Vision LiteGlazing that is mounted in a door.


Wall AngleAn angle of the guide assembly, which attaches to the face of the wall and supports the load of the door assembly.
Wind BarChannel or bar attached to the guide, which engage windlocks under wind load.
WindlockA component attached at predetermined intervals to slat ends to prevent curtain from leaving the guides under wind load, and which is used in conjunction with wind bars inside the guides.
Working TurnsThe additional winding of the springs as the barrel rotates and the curtain closes.


"Z" GuidesCommon expression for the shape that guides from when they are mounted to masonry jambs.
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