Knowledge Base:  
Garage Door Terminology
Last Updated: 03/06/2011
TDS 160 Sectional Garage Door Terminology

Garage Door Terminology

Astragal Retainer: See Bottom Weatherseal

Automatic Latch: An automatic door locking device

Automatic Opening Device: Quick opening mechanism recommended for installations requiring rapid automatic door opening without use of an electric operator

Back Hang: Hanger fabricated from angle iron, which attaches the end of the horizontal tracks to roof construction or ceiling

Back Jamb: Wood member on the inside surface of the garage, surrounding the door opening

Backroom: Horizontal distance measured into a building from the face of the header above a garage door opening to the first obstruction at the required headroom

Ball Bearing: A load bearing device that uses trapped rolling balls to reduce rotating friction

Ball Bearing Drum: Counterbalance drum with a ball bearing for smoother operation of heavier doors

Bar Joist: A lightweight truss adaptable for the support of roof decks

Bead: A strip of metal, vinyl, or rubber used to secure glass around the periphery of a pane

Black: Color-marking convention to mark parts as Right Side, Left Wound

Blind Rivet: A type of fastener that mechanically joins two pieces of material together by means of a riveting tool

Booster Spring: Additional spring, usually an extension spring, provided to compensate for weakened counterbalance

Bottom Bracket: See Bottom Corner Bracket

Bottom Corner Bracket: A structural support located on the bottom section that holds track rollers and may also provide for attachment of lifting cables

Bottom Corner Fixture: See Bottom Corner Bracket

Bottom Fixture: See Bottom Corner Bracket

Bottom Rail: The lower-most horizontal rail of a door section

Bottom Roller Bracket: See Bottom Corner Bracket

Bottom Weatherseal: Weatherstrip attached to the bottom rail of a door to seal against the floor

Bow: Condition where a garage door bottom rail of a wood door is not level or straight, which is characterized by a closed door “smiling” (corners turned up)

Box Strut: See Strut

Bracket Mounted: Method of fastening vertical track to jamb using angle brackets

Bracket-Mounted Track: See Bracket Mounted

Breakaway Track: See Angle Mounted Track

Breakstem Rivet: See Pop Rivet

Broken Cable Device: A bottom fixture intended to prevent a door from falling in the event of cable breakage

Buck: See Back Jamb

Bushing: A fixed or removable lining used to constrain, guide, or reduce friction

Cable: See Aircraft-Type Cable

Cable Clamp: Manufactured device used to secure two pieces of cable to each other

Cable Drum: Grooved drum, fitted on torsion spring shaft, onto which lifting cable is wound when door is opened

Cable Drum Set Screws: Normally refer to set screws that attach the drum to the shaft/tube. One screw may secure the cable to the drum in order to secure proper cable length.

Cable Length: Specific amount of cable required to properly operate door

Cable Safety Device: A bottom fixture designed to slow or stop the descent of a door in the event of a cable breakage

Cable Stop: A swaged fitting at the end of the cable to prevent slippage through a slot in a drum

Cable Stopping Device: See Broken Cable Device

Cam: Rotating piece that transfers rotary motion into linear motion

Cam Tube: Tube encasing a torsion spring assembly that imparts axial force

Carry-Away Post: A type of removable center post

Ceiling: Top horizontal surface in the interior of a garage

Center Bearing Bracket: A bracket that houses a shaft bearing and aligns and supports the torsion shaft and spring(s) assembly. Also serves to anchor stationary cone(s) to header

Center Bearing Plate: A plate or bracket that can house a shaft bearing and is used to align and support the counterbalancing mechanism to the torsion shaft as well as anchor one end of torsion springs to the header.

Center Bearing Support: See Center Bearing Bracket

Center Bracket: See Center Bearing Plate

Center Bushing: Metal or plastic bushing used with a center bracket to support a torsion tube

Center Cable: See Center Lift Cable

Center Clamp: See Center Lift Cable

Center Coupler: See Coupler

Center Coupling: See Coupler

Center Hinge: A hinge generally located on the intermediate stiles to allow sections to pivot as door opens. Also used as graduated edge hinge between bottom and intermediate section

Center Lift Cable: Additional cable assembly which is secured to outside of door at points toward the center of the door, used to provide extra lifting support for extremely wide or heavy doors.

Center Post: The vertical building structure (or member) between two single car doors, or a vertical reinforcement usually installed for high wind events. Sometimes also used to refer to a Vertical Post.

Center Stile: Vertical member of a door section which provides structural rigidity and location for center hinge attachment

Center Support Bearing: See Center Bearing Bracket

Center Support Track: See Center Track

Center Track: Added track giving additional support to preventing sagging of a door in the open or horizontal position. Often used with an exceptionally wide door, a heavy door or a door containing a pass door

Chain Hoist: Refers to sprocket or pocket wheel, connected to torsion spring shaft, imparting mechanical advantage to open and close a door

Chain Hoist Operator: Jackshaft type operator to which chain hoist is attached

Channel Frame: Frame used in jamb construction consisting of steel channel shapes installed where the flanges of the shapes wrap around the corners of jambs

Channel Truss: See Strut

Chill: A square shaft that connects an outside handle to an inside lock set or night latch

Clearance: The amount of side room, head room and back room required to properly install a sectional door

Clear Rail: See Solid Rail

Clevis: See Sheave Fork

Clevis Pin: A steel pin used in conjunction with a cotter pin to hold a counterbalance cable to a bottom bracket or an operator arm to an operator bracket

Commercial: A sectional overhead type door which is intended for vehicular use at entrances of buildings such as loading docks and service stations, and is normally operated less than 5,000 cycles per year

Containment Cable: A cable threaded through an extension spring to retain the spring if it breaks

Continuous Angle: See Reverse Angle Mount

Continuous Angle Mount: See Angle Mounted Track

Contour Track: Horizontal track that follows the contour of roof construction or ceiling

Corner Bracket: See Bottom Corner Bracket

Corner Burn: A full-scale fire test performed in a specially constructed room, where the ignition source is located in the corner of that room, adjacent to the garage door

Cotter Pin: A half-round metal strip bent into a pin, whose ends can be flared after insertion through a slot or hole

Counterbalance: To oppose or balance with an equal weight or force

Counterbalance Shaft: See Torsion Shaft

Counterbalance System: A system which counteracts the weight of a garage door to allow a reduced force to open and close the door

Counterbalance Tension: See Counterbalance

Counterweight: Design of door mechanisms using weights instead of springs to counterbalance door weight

Counterweight Balancing System: See Counterweight

Coupler: A device to connect two counterbalance shafts together, end-to-end

Coupling: See Coupler

“C” Strut: See Strut

C-Value: Heat rate flow through an insulating material when there is a temperature difference from outer to inner surfaces; not normally used in conjunction with thermal transmittance through garage doors

Cycle: One complete cycle of a door beginning with the door in the closed position, then moving to the open position and back to the closed position

Cylinder: The part of a key operated lock that accepts the key and contains the locking pins

Daylight Opening: Opening dimensions taken between face of jambs and between floor and header

DC: Door opening size designation, denoting “double car”

Dead Coils: The number of coils rendered inactive by the spring plugs

Dead-End Cone: See Stationary Cone

Dead in the Head: The lack of counterbalancing when the door is in the open position, failing to keep the door fully open

Dead Load: A static applied load, or a load without movement, generally referring to the weight of the door

Decal: A template of information attached to a garage door, or in its vicinity, to convey relevant information concerning the garage door system

Decorator Angle: See Jamb Angle

Depth: See Backroom

Design Wind Load: Horizontal design load applied to a garage door based on such factors as wind speed, building height and door horizontal location

Direct Drive Chain Hoist: See Chain Hoist

Disconnect Chain: Used in conjunction with industrial door operators to disengage operator and permit manual use of emergency hand chain to facilitate operation of door in event of power failure

Disconnect Hoist: See Disconnect Chain

Door Casing: The framing members with which a door opening is finished

Door Check: A mechanical device to insure the self closing of a pass door or wicket

Door Closer: A device, combining in one case, a spring to close the door, and a checking arrangement to prevent slamming and to insure silent closing

Door Frame: The frame into which the door fits; consists of two door jambs, and a door header

Door Framework: See Door Frame

Door Guide: See Track

Door Header: The upper part of a door frame, consisting of the head jamb, head casing, stop and trim molding

Door Jamb: The upright framing on each side of the door opening

Door Moulding: See Door Casing

Door Opener: See Electric Operator

Door Opening: See Daylight Opening

Door Operator: See Electric Operator

Door Path: See Trajectory

Door Schedule: A list of door sizes, locations and special requirements shown on a construction document

Door Section: A single segment of a sectional door

Door Size: Door dimensions characterized by the width first and the height second

Door Stop: See Stop Mould

Door Travel: See Trajectory

D Shaft: A torsion shaft manufactured with a flat area allowing minimum rotation of affixed hardware.

Double Door: Commonly used to refer to larger width doors used on two car openings

Double End Stile: When a door section utilizes two stiles adjacent to each other on each end of the section

Double Glazing: Use of two thicknesses of glazing within an opening to improve insulating value and/or reduce sound transmission

Double Low Headroom Track: See Double Track Low Headroom

Double Shaft: Double torsion spring shaft used when additional space is required to accommodate counterbalance spring lengths

Double Strength Glass: A grade of window glass lighter than plate glass and usually 1/8” thick

Double Thick Glass: See Double Strength Glass

Double Top Roller Fixture: Fixture used at the top section consisting of two top brackets to incorporate a longer roller shaft. Usually requires double end stiles on top section

Double Track Low Headroom: Addition of second pair of horizontal tracks to reduce the high point of travel of top section and permit door being mounted in area with minimum headroom facilities

Dowel: Wooden pin for fastening wood usually glued in between stiles and rails to strengthen a joint

Drawbar Operator: Electric operator which mounts above the door in the horizontal position and lifts door by pulling and pushing the top section. For normal headroom and low headroom doors

Drip Cap: A projection over the head of a door opening, or on the top of a wall, to throw water clear of the building

Drip Lap: An angled weather seal provided between sections on steel doors in lieu of a rabbeted joint to prevent entrance of the elements

Driveway Post: Post mounted adjacent to a residential driveway to provide exterior location for key switch to actuate an automatic door operator.

Drop-Off Weight: See Counterweight

DSB: Acronym for Double Strength Grade B Glass

Duplex Spring: A combination of two torsion springs of different diameters telescoped within spring fittings

Eased Edge: Rounded and sanded meeting rail edge

Eased Off: See Eased Edge

Eave Height: Height measured from the floor to the underside of an eave

Edge Grain: Wood in which the rings form an angle of 45 degrees or more with the surface of the pieces

Edge Hinge: See Graduated Edge Hinge

Electric Opener: See Electric Operator

Electric Operator: An electrically-powered device to control the opening and closing of a door

Electrical Interlock: Interlock to prevent door operation by an electric operator under certain conditions

Embossed Door Section: Door section featuring embossed panels

Embossed Panel: Panel containing surfaces raised in relief from a flat surface

Embossed Rosette: Special ornament or design accessory made of wood, hardboard or aluminum with designs raised in relief from the surface

Embossed Section: See Embossed Door Section

Embossed Steel Door Section: See Embossed Door Section

End Bearing Plate: Plate commonly used on torsion spring counterbalance units, which includes a ball bearing to support radial movement of a torsion shaft at each end

End Bearing Support: See End Bearing Plate

End Bracket: See End Bearing Plate

End Hinge: See Graduated Edge Hinge

End Roller Hinge: See Graduated Edge Hinge

End Stile: Stile located at each end of a door section which provides for attachment of graduated edge hinges

End Stile Lock: See Inside Lock

End Stile Sealing Strip: Foamed plastic strip to seal sections at end stiles of steel and fiberglass doors

Escutcheon: A plate surrounding the lock mechanism on outside of door

Exhaust Port: Opening in bottom section to accept hose to vent tailpipe exhaust

Extension Spring: Provides power or tension by stretching or pulling, and is usually mounted along the horizontal section of track extending from front of door opening to the back hang

Exterior Lock: Keyed lock on exterior of the door

Extrusion: Fabricated shapes made by forcing hot aluminum, or plastic, billets through a die in an extrusion press

False Louver Molding: Special angular shaped molding that gives an appearance of a slatted panel when fitted together

Faux Divided Lite: One piece of glass divided by muntons to appear as several lites.

Ferrule: Metal ring or cap which is affixed to a cable by compressing so as to form a button or loop on the end of the cable

Finger Joint: Joint used in joining lumber together at ends of lumber pieces

Finish Moulding: See Stop Mould

Finished Door Opening: See Daylight Opening

Finished Opening: See Daylight Opening

Fire Station Release: See Automatic Opening Device

Flag: See Jamb Angle

Flag Angle: See Jamb Angle

Flag Bracket: See Jamb Angle

Flame Spread Index: A measurement of horizontal flame spread across a product specimen under controlled laboratory conditions; the product is compared to the performances of red oak, which is standardized to 100, and gypsum board, which is standardized to zero

Flipper: See Automatic Latch

Floor Seal: See Bottom Weatherseal

Floor Step: See Rain Stop

Flush Design: See Flush Door

Flush Door: Door comprised of sections unbroken by visible rails and stiles where the facing of the entire door presents an even surface

Follow Roof-Line Hardware: See Contour Track

Follow-the-Roof Pitch: See Contour Track

Follow-the-Roof Track: See Contour Track

Front Mounted Low Headroom: Low headroom hardware where springs mount on torsion shaft above opening

Front-Mounted Spring: A counterbalance spring that is mounted to the header above the door

Full Vertical Lift: See Vertical Lift

Full View Section, Full Vision Section (A totally glazed section with various types of glass or clear plastic. Section formed of aluminum extrusions which will marry with steel or aluminum sections above and below)

Full Vision Section: See Full View Section

Galvanizing: Zinc coating to protect steel against corrosion

Garage Door Opener: See Operator

Garage Door Operator: See Operator

Gauge: U.S. Standard, established by congress in 1893, specifying that weight per square foot would be indicated by a numbering system; larger numbers indicate smaller thicknesses and vice versa

Glazed: Fitted with panes of glass or clear plastic

Glazing Lite: See Vision Lite

Glazing Strip: Extruded plastic or rubber strips that fit against glazing and window frame to resist water infiltration

Graduated Edge Hinge: Hinge placed on edge of door sections allowing sections to pivot as door opens and closes. Hinges hold track roller and are graduated and numbered for correct placement to ensure flush fit of door against jambs when closed

Grease Packet: Lubricant enclosed in a small packet

Grille: Insert within a window, designed to give the appearance of divided lites

Guard Angle: See Track Guard

Gusset: Cast, extruded, stamped, or rolled aluminum corner reinforcement which is fastened in corners to stiffen joints or corners

Gusset Plate: Hardware fastened to door header to help support the track assembly and spring assembly

Hang Down: The amount of the door that hangs down from the door opening when the door is in the open position

Hanging Iron: See Angle Iron

H-Column Jamb: Separation of two door openings where door track is to be mounted directly to H-Column

Header: See Door Header

Header Seal: See Top Seal

Headplate: The supporting plate for the lifting drum located in line with the outer edge of the door

Headroom: Vertical clear space required inside above the door opening, and below the lowest ceiling obstruction, required for proper operation of the door and its hardware

Heliarc Weld: A type of inert gas-shielded arc welding employing helium or argon

High Arc: See Trajectory

High Cycle Spring: Counterbalance springs with increased cycle life capability for high usage doors

High Lift: Distance from header to underside of horizontal track, when high lift track is required

High Lift Drum: A cable drum contoured to balance a high lift door

High Lift Track: Track and hardware that causes the door to rise vertically some distance above the top of the door opening before it levels out into a horizontal position

High Moment Arm: Radius of a cable drum, including cable, at point of cable peel off from the drum

High Trajectory: See Trajectory

Hi-Lift: See High Lift

Hi-Lift Track: See High Lift Track

Hinge: Hardware item that joins door sections together, and allows sections to pivot independent of each other

Hinge Support Plate: Plate used to support the hinge mounting area, i.e. a backup plate

Hinge Tube: Tube used to connect two hinge leafs together

Hoist Electric Operator: Similar to a jackshaft-type operator but with an auxiliary emergency chain hoist in case of a power failure

Horizontal Angle: See Horizontal Track Angle

Horizontal Radius: Section of track that transitions from vertical to horizontal track welded, bolted or riveted to the horizontal track and then bolted to the flag angle

Horizontal Reinforcing Angle: See Horizontal Track Angle

Horizontal Rise: The upward slope of the horizontal track which helps to start the door downward and helps maintain cable tension

Horizontal Track: Track used in the horizontal segment of a track assembly

Horizontal Track Angle: An “L” shaped angle affixed to the horizontal track to stiffen it

Horizontal Track Assembly: An assembly made up of horizontal track and reinforced with an angle that is used to both guide and support the door in the horizontal position

Horizontal Track Radius: See Horizontal Radius

Hot Off The Floor: Condition where the door has a tendency to lift off the floor

Inch-Pounds: English unit of measurement of torque

Inclined Track: Tapered spacing of the vertical track away from the jamb, permitting weathertight closing of door against jamb and easy release for opening door by eliminating friction

Inside Hook Up: Connection where the counterbalance cable is on the inside of the track, between the door sections and the vertical track

Inside Hook Up Bottom Bracket: Bottom corner bracket where the cable is routed between the vertical track and the door sections

Inside Lock: Spring loaded, sliding deadbolt lock or spring latch operable only from interior of the door

Installation: Placing a door in position for use

Installer: Person placing the door in position for use

Insulated Door: Door sections containing insulating material

Insulating Glass: Multi-pane glass assembly containing air space between panes for insulation

Insulation: Material having ability to reduce heat or cold transmission

Interior Lock: See Inside Lock

Intermediate Hinge: See Center Hinge

IPPT: Acronyn for Inch-Pounds Per Turn; torque rate of a spring, indicating the number of inch-pounds of torque delivered to a shaft for each turn the spring is wound

ISLO: Acronym for “inside looking out”

Jackshaft-Type Operator: Operator which is mounted on wall or ceiling, with drive provided to turn a torsion shaft

Jamb: See Door Jamb

Jamb Angle: See Angle Mounted Track

Jamb Bracket: “L” shaped bracket used to connect the vertical track to the door jamb

Jamb Extension: Framing extensions of door jambs above opening height; required to support door track and spring assemblies

Jamb Guard: See Track Guard

Jamb Seal: See Stop Mould

Joint, Rabbeted: See Joint Shiplap

Joint, Shiplap: A raised back portion of a section joint, fitting with a lowered front portion of a section joint, to create a weathertight seal between door sections

Joint, Tongue-and-Groove: A joint with an interior raised portion, fitting with a joint with an interior lowered portion, to create a weathertight seal between door sections

Joint Bracket: See Splice Jamb Bracket

Joint Seal: See Section Joint Meeting Rail Seal

Keeper Plate: See Striker Plate

Key: A square piece of steel that slides into a key way to prevent parts from rotating on a shaft

Key Alike: See Keyed-Alike

Key Switch Control: Use of key switch to actuate a door operator in place of or in addition to a push-button or transmitter

Key Way: A groove, milled into an object, which when used with a key will prevent parts from rotating on a shaft

Keyed-Alike: Two or more lock cylinders intended to be opened with the same key

Keyed Shaft: A shaft that has an integrated key way

K-Value: Laboratory-determined value of thermal conductance of a material

“L” Strut: See Strut

Lag Screw: A heavy wood screw with a square or hex head and a coarse thread

Lap Jamb: Condition where door sections lap the door opening on each jamb

Lapped Joint: See Joint, Shiplap

Latch Lock: See Automatic Latch

Lateral Force: Force applied from or toward the side

Lift Bracket: See Bottom Corner Bracket

Lift Clearance: See High Lift

Lift Clearance Track: See High Lift Track

Lift Handle: Handle for manually operating a sectional door

Lift Plate: See Step/Lift Plate

Lintel: Beam provided over an opening to carry wall and/or roof loads over an opening

Lite: See Vision Lite

Lock: Device to secure door to vertical track(s) in the closed position

Lock Bar with Cremone: Rotating the cremone or lock bar disc from outside or inside will force lock bars into cut-outs in track to lock door

Lock-On Bottom Roller Bracket: See Bottom Corner Bracket

Lock Strike: See Striker Plate

Long-Stem Roller: Roller with a shaft length of 7 inches or longer

Louver: An opening with slats or screening for ventilation

Low Headroom Hardware: See Low Lift Hardware

Low Lift Hardware: Low headroom accessories which enable a door system to operate in minimal headroom conditions

Low Moment Arm: Smallest radius, or distance from the shaft axis, to the center of the cable that regards cable peel off point on cable drums

LSLO: Acronym for left side looking out

Lubricant: A substance used to lubricate

Lubricate: To make a surface smooth or slippery; to reduce friction

Maintenance: The act of keeping a door system in good working condition

Master Keyed: See Master Keying

Master Keying: Arrangement whereby cylinder locks, although fitted with different keyed cylinders, can be opened or locked by means of one master key

Meeting Rail: The top horizontal rail or bottom horizontal rail of any section that meets and joins to form a weatherproof seal

Metallurgist Report: A report or document that describes the composition of a metal

Mill Certification: A report or document from the producing mill that provides all pertinent data relative to the composition, structure, heat, etc. of a given metal

Minimum Headroom: See Headroom

Minimum Sideroom: See Sideroom

MIP: Acronym for Maximum Inch-Pounds; (IPPT x Turns = MIP); Used to describe the total torque required on a shaft to raise a given door weight from the floor, and also is the measurement of the torque capacity of a particular wire size at a desired cycle level of operation

Modular Coordination: The dimensioning of building units so that they will fit together, and the use of building dimensions consistent with such coordinated sizes.

Mounting Plate: Flat steel or wood member placed on the wall to accommodate spring supports, spring shaft bearings, chain hoists and mounting for operators

Movable Post: Post designed to allow the use of two or more doors in a single opening with carry-away aluminum center posts that can be removed when doors are in up position.

Mullion, Garage Door: A vertical post used as a door reinforcement

Mullion, Window: Framing member forming a divide between units of a window

Muntin: A bar member supporting and separating panes of glass within a sash or door

Munton, Window: Munton that defines a faux divided lite.

Mutt: See Stile

Neoprene: A synthetic rubber made by polymerizing chloroprene

Nicopress Sleeve: A two-hole aluminum or copper sleeve through which cable is passed. Swaging will upset the sleeve to form a loop at cable end

Normal Headroom: See Headroom

Normal Sideroom: See Sideroom

Numbered Hinge: See Graduated Edge Hinge

Numbered Panel: Area between stiles I.S.L.O. numbered left to right

Numbered Roller Bracket: See Graduated Edge Hinge

Numbered Section: See Door Section

Nylon Center Bearing: See Bushing

Oil: See Lubricant

Oil-Canning: A slight buckling in sheet metal, causing the appearance of waviness or unevenness

Opener: See Operator

Opening Height: Distance from floor to the bottom of header

Opening Size: See Daylight Opening

Opening Width: Distance between jambs of the door opening

Operator: Electric device used to control the up and down motion of the door

Outside Hook Up: Connection where the counterbalance cable is on the outside of the tracks

Outside Hook-Up Bottom Bracket: Bottom corner bracket where the cable is routed outside the tracks

Outside Pull: See Outside Hook Up

Overlay: Decorative ornaments of metal, wood or hardboard used for outside decoration of garage door sections

Pan Door: A garage door composed of sheet metal door sections

Panel: A raised and decorative design on door sections

Pass Door: A swinging pedestrian door built into a sectional door. Not recognized as an exit door by model codes

Pedestrian Door: Access door adjacent to upward acting doors. Used as a legal means of egress to avoid the use of a sectional door

Perforated Angle: Angled metal with a serried of punched holes used to hang garage doors and operators

Perimeter Seal: Weatherstrip installed at the perimeter of a garage door

Pinch Resistant: Term for a door that has been designed to prevent entrapping, crushing, breaking, severing or dislocating a person’s finger

Plastic Muntin: See Muntin

Pocket Wheel: A wheel or drum machined to receive the individual links of a chain; used to directly transmit power

Polyurethane: A type of foam insulation commonly foamed in place by manufacturers of garage door sections

Pop Rivet: See Blind Rivet

Pounds Pull: Unit of force determined by dividing the torque by the moment arm of the drum

Power Unit: A complete torsion spring assembly consisting of springs, shaft, winding plugs and stationary cones, drums and cables

Pre-Finished: Finish characterized by galvanized steel painted with a primer, then given an oven-baked top coat

Pre-Painted: See Pre-Finished

Prime: To lay on the first coat of primer paint

Prime-Painted: Coated with primer paint

Pull Down Rope: A rope connected to the bottom bracket; used to manually pull the door down

Pull Rope: See Pull Down Rope

Pull Type Spring: See Extension Spring

Pulley: A wheel turning around an axis and having a groove on its rim in which runs a cable, chain, or rope

Pulley Clevis: See Sheave Fork

Punched Angle: See Angle Iron

Punched Angle Brace: See Angle Brace

Punched Angle Iron: See Angle Iron

Punched Angle Track Hanger: See Back Hang

Purlin: A horizontal roof member spanning between beams and trusses to which roofing is attached; commonly used in a pre-engineered, industrial type building

Push Down Spring: Spring-activated push rods mounted on horizontal tracks to start door down during closing portion of door cycle; generally used with a jackshaft-type operator or a manual chain hoist

Pusher Bumper: A leaf spring in place of a rod

Push Nut: Stamped metal fastener designed to be pushed onto a shaft to secure an assembly

Quarter Grain: See Edge Grain

Quarter Round: Molding showing a quarter circle in its cross section

Quarter Turn: A unit of turn measurement when winding tension into a torsion spring

Quick Turn Bracket: See Low Lift Hardware

Radial Force: A force generated from the center of an object toward the outside

Radius: See Horizontal Radius

Radius Track: See Horizontal Radius

Rail: Horizontal member of a section

Rain Ledge: See Rain Stop

Rain Stop: Ledge provided at the point where the bottom rail meets the floor to prevent water from running under the door and allowing for runoff of the water onto the drive or approach

Raised Panel: See Panel

Rate of Rise: Measurement of change per revolution of a drum's moment arm

Rear Mount: When the counterbalance system attached to the rear of the horizontal tracks

Rear-Mounted Torsion: See Rear Mount

Rear Track Hanger: See Back Hang

Red: Indicates color for Left Side, Right Wound

Regular Angle Mount: See Angle Mounted Track

Removable Center Post: Post/track assembly which substitutes for door jamb in wide door openings so that multiple doors may be used instead of a single large door, and which can be released and carried from an opening

Removable Jamb Wall: Wall designed to allow the use of two or more doors in a single opening with carry-away aluminum center posts that can be removed when doors are in up position

Removable Mullion: See Removable Center Post

Removable Post: See Removable Center Post

Residential: A sectional overhead type door which is intended for use in a residential garage, and normally operated less than 1,500 cycles per year

Restraining Cable: See Containment Cable

Return: See Sideroom

Reverse Angle: See Reverse Angle Mount

Reverse Angle Mount: An “L” shaped angle with the wall leg toward the door opening used to connect the vertical track to the jamb. Used in low headroom and sideroom restricted garages as well as lap joint.

Rigid Strut: See Strut

Rigid Truss: See Strut

Roll-Away Post: See Removable Center Post

Roller: See Track Roller

Roller Assembly: See Track Roller

Roller Bracket: A device that is mounted to a door section and holds a track roller

Roller Stem: See Track Roller

Rounded Off: See Eased Edge

RSLO: Acronym for “right side looking out”

R-Value: Thermal resistance value; inverse of U-Value

Safety Bottom Bracket: See Broken Cable Device

Safety Bottom Corner Bracket: See Broken Cable Device

Safety Bottom Fixture: See Broken Cable Device

Safety Cable: See Containment Cable

Safety Spring Containment: See Containment Cable

Safety Spring Containment Kit: See Containment Cable

Sash: The framework which holds the glass in a window or door

Sash Muntin: One of the rabbeted bars into which glass is fitted in a sash containing two or more lights

SC: Door opening size designation, denoting “single car”

Scarf Joint: Method of joining pieces of lumber together by gluing and pinning with wood dowels

Scribing: Cutting a door bottom rail to match the contour of the floor

Scutcheon: See Escutcheon

Section: Garage door component that extends the full width of an opening; usually joined together by hinges

Section Joint Meeting Rail Seal: A weather seal between door sections

Section Joint Meeting Rail Type Seal: See Section Joint Meeting Rail Seal

Sectional Door: See Sectional-Type Door

Sectional-Type Door: Door made of two or more horizontal sections hinged together so as to provide a door capable of closing the entire opening and which is by means of tracks and track rollers

Servicing: See Maintenance

SG: Refers to “single glazed”

Shaft Bearing: A bearing that is used to maintain torsion shaft alignment and reduce friction

Sheave: A metal or plastic pulley that is designed to guide the cables employed in a counterbalance system

Sheave Fork: A yoke type device used to attach the sheave to extension springs

Shiplap Section Joint: Section joint interface that steps up from one level to a second level from the front of the door to the back of the door

Shoe Molding: See Quarter Round

S-Hook: Hardware device used to connect an extension spring to a pulley. These are also used with other door related hardware (i.e. chain on locks)

Shop Drawings: Drawings provided by the manufacturer or door supplier to the architect-engineer showing the plans, sections, elevations, and details of the work required, submitted to assure proper interpretation of the intent of the architectural drawings

Side Bearing Plate: See End Bearing Plate

Side Seal: See Stop Mould

Sideroom: A horizontal measurement from each side of the door opening, outward to the nearest obstruction Single Door: Commonly used to refer to smaller width doors used on one car openings

Single Strength Glass: See Single Thick Glass

Single Thick Glass: A type of sheet glass used in glazing sashes

Slant: The pitch of a roof

Smile: See Bow

Snap Latch: See Automatic Latch

Solar Glass: A type of tinted glass

Solid Rail: A rail made with one continuous piece of lumber without finger joints

Special Door: Non-standard door which must be custom manufactured and/or specified

Specifications: A detailed statement of the quantity and type of material to be used in the construction of a garage door system

Splice Plate: Plate used for attachment of track at the junction of tracks in clip type angle mounted track

Spring Anchor: See Center Bearing Bracket

Spring Anchor Bracket: See Center Bearing Bracket

Spring Anchor Cone: See Stationary Cone

Spring Anchor Plate: See Center Bearing Bracket

Spring Assembly: See Torsion Spring Assembly

Spring Assembly Closed Wound: A coiled torsion spring with no gaps between the coils

Spring Assembly Open Wound: A coiled torsion spring with equal gaps between each coil

Spring Balance: The amount of turns needed to counterbalance the weight of the garage door

Spring Bumper: Spring mechanism mounted on horizontal track that eases the door to stop in its upward travel to reduce shock and prevent pull down rope breakage. Can be made from leaf springs or tension rods.

Spring Constant: Mathematically developed number from basic spring wire formulas, that applies to any specific wire size and coil diameter combination; used to determine the number of active coils a spring must contain

Spring Containment Device: See Containment Cable

Spring Fitting: A plug or cone used to adapt the torsion springs to the torsion shaft and/or center bearing bracket. One piece is a stationary cone while the other fitting is a winding plug

Spring Hook: See S-Hook

Spring Latch Lock: See Automatic Latch

Spring Pad: Pad installed on header above the door to anchor the center bearing bracket. Can be mounted in various locations, not necessarily in center, depending on size of springs

Spring Plug: See Spring Fitting

Spring Retainer: See Spring Fitting

Spring Winding Cone: See Winding Plug

Square Key: See Key

Standard Headroom: See Headroom

Standard Sideroom: See Sideroom

Stationary Bearing Retainer: See Stationary Cone

Stationary Cone: Part that fits into the end of a torsion spring permitting the spring to be fixed to the center bearing bracket. May also incorporate a retainer for a ball bearing or bushing

Stationary Plug: See Stationary Cone

Stationary Sleeve: See Stationary Cone

Stationary Spring Cone: See Stationary Cone

Steel Jamb: Door framing made from either channel or angle iron

Steel Jamb Mounted: A track system intended for mounting to a steel jamb

Steel Pin: Short, headless pointed nail driven through the dowel and rail in doors for greater security

Step Down Plate: A means of closing a sectional door the last few inches of its travel

Step/Lift Plate: A part that can be used as a step down plate and a lift handle for manually operating a sectional door

Sticker: See Decal

Stile: Vertical reinforcement member of a section

Stock Door: Door made to standard size and generally kept in inventory at either distributor or factory warehouse

Stop: See Stop Mould

Stop Mould: Serves to seal the perimeter of the door against weather and light infiltration; usually nailed to the jamb, outside the door

Stop Moulding: See Stop Mould

Stress: The amount of work required of a spring at a desired cycle level

Stretch Spring: See Extension Spring

Strike: See Striker Plate

Striker: See Striker Plate

Striker Plate: A plate used in conjunction with a locking system to secure a lock mechanism

Strut: Support stiffener to reduce deflection of the door sections in the horizontal position. Also, to increase windload capability of a door

Sway Brace: See Angle Brace

Sway Strap: See Angle Brace

Sweep: See Trajectory

Swing-Away Post: A type of removable center post that remains attached at the top and can be pivoted out of the way

Swing-Up Post: See Swing-Away Post

T Handle: A handle in the shape of a “T”

T Lock Handle: See T Handle

Tapered Vertical Track: See Inclined Track

TC: A designation of door opening size indicating an opening for two cars

Template: A pattern used as guide to shape something or show hole drilling locations. Also a short header to support a beam in a wall

Test Load: See Test Wind Load

Test Wind Load: Specified difference in static air pressure (positive or negative), equal to a specified percentage greater than or equal to 100% of the design load

Thermal Barrier: See Thermal Break

Thermal Break: The separation between the outer and inner surfaces of a door section

Thermal Seal: See Bottom Weatherseal

Tin-Canning: See Oil-Canning

Tog-L-Loc: Method of mechanically securing two pieces of steel together without welding, riveting or bolting

Tongue and Groove Section Joint: Section joint interface commonly composed of a middle protrusion on a garage door section edge mating with a middle groove on an abutting section edge

Tongue and Groove Board: Vertical wood planks that when laid out side-by-side resembles wainscoting.

Top Carrier: See Top Fixture

Top Fixture: A bracket for positioning the top guide roller on the top section of a door

Top Header Seal: See Top Seal

Top Rail: Horizontal rail forming the top of a door as distinguished from the meeting rails and bottom rail

Top Roller Bracket: See Top Fixture

Top Roller Fixture: See Top Fixture

Top Seal: Weatherstripping which fastens to the top of the door to seal the door along the top of the opening

Torque: The twisting force around an axis

Torque Bar: See Torsion Shaft

Torsion: Act of twisting or turning of a torsion spring by the exertion of forces tending to turn one end about a longitudinal axis while the other end is held stationary

Torsion Bar: A long metal bar that transfers torque from a spring to a winding plug

Torsion Shaft: A shaft that transfers torque from springs to load

Torsion Spring: A spring that works in the manner of twisting one end or part about a longitudinal axis while the other end is held or turned in the opposite direction developing torque

Torsion Spring Assembly: Hardware used to make up door counterbalance assembly

Torsion Spring Counterbalance Assembly: See Torsion Spring Assembly

Torsion Tube: See Torsion Shaft

Torsion Tube Coupler: See Coupler

Track: Channel shaped metal bars or rails in which upward acting doors operate via track rollers

Track Bracket: A fixture, connected to a track, which is designed for the track to be mounted to the jamb

Track Clip: A metal plate used to attach tract to wall angle

Track Graduation: The differential distance from the track to the door jamb, measured at the top and bottom of the vertical track

Track Guard: Added protection for back of vertical track recommended in cases where powered material handling fork trucks and similar equipment may be operating in the area.

Track Hanger Kit: See Back Hang

Track Radius: See Horizontal Radius

Track Roller: Roller assembly for guiding the door sections along track

Trajectory: The arc of travel or sweep of the top section as the door is raised from closed to open position

Translucent Door: Door that allows the passage of light without being transparent

Transom Bar: A horizontal crossbar in a window, over a door, or between a door and a window or fanlight

Transom Section: An extra section above a garage door opening sometimes used to allow extra lift of the horizontal tracks to accommodate a trolley type operator

Trim: The finishing materials; such as the lock and handles on the door

Triplex Spring: Three springs of increasing diameter assembled one inside another using special spring fittings

Trolley Opener: See Drawbar Operator

Trolley Type Operator: See Drawbar Operator

True Divided Lite: A window composed of several smaller windows separated from each other by window mullions

Truss: See Strut

Truss Bar: See Strut

Tubular Shaft: A hollow shaft

Turn: A 360-degree revolution of a component about its axis

Turns On Spring: See Winds On Spring

Twist: A form of warp caused by the twisting or winding of the edges of a rail

U-Bar: See Strut

U-Bar Stiffener: See Strut

U-Bar Truss: See Strut

Urethane (Finish): A clear finish commonly used as a top layer to finish wood

Urethane (Insulation): See Polyurethane

“U” Strut: See Strut

U-Value: Thermal transmission coefficient which is a measurement of heat, in BTU's, transmitted through one square foot of material (the door) in one hour at a temperature difference of 1 degree from one side to the other

Upper Trajectory: See Trajectory

Upper Vertical Track: Upper track assembly on a vertical lift door

Varnish: Glossy clear top coat used on finished wood; may not be suitable for outdoor wood applications for its lack of breathability

Vent: An opening located in the bottom section of a door for ventilation

Vertical Grain: See Edge Grain

Vertical Lift: Refers to a hardware design that causes doors to open vertically where no horizontal tracks are required

Vertical Lift Drum: A cable drum with changing radius grooves to negate spring tension

Vertical Post: A vertical reinforcement sometimes installed for high wind events

Vertical Splice Angle: See Jamb Angle

Vertical Track: The portion of track that is oriented vertically and is adjacent to the jamb

Vertical Track Assembly: An assembly made up of a piece of vertical track and a piece of continuous angle or jamb brackets used to secure the track to the jamb.

Vision Lite: Glazing that is mounted in a door

Warning Tag: A tag with warnings and/or instructions for safe operation

Water Seal: A coating of some kind used to prevent the absorption of water

Water Stop: See Rain Stop

Weather Joint: See Weatherstrip

Weatherseal: See Weatherstrip

Weatherstrip: Material used at the perimeter of a garage door, or between joints of a garage door, intended to improve a door’s performance against air infiltration and thermal transmission

Wedge Connection: A device composed of a steel wedge and clip for securing the joint between vertical and horizontal track sections

West Coast Lumber: Lumber produced on the West Coast, generally used in manufacturing wood sectional garage doors

Wheel and Axle: See Track Roller

Wicket Door: See Pass Door

Wind Load: See Design Wind Load

Winding Bar: See Winding Rod

Winding Cone: Part that fits into a torsion spring permitting winding and tension adjustment

Winding Cone Set Screw: See Winding Plug Set Screw

Winding Cone Socket Head Set Screw: See Winding Plug Set Screw

Winding Plug: See Winding Cone

Winding Plug Set Screw: Set screw fasteners used to lock the winding plug to the torsion shaft

Winding Rod: A solid rod that fits into the socket of the winding plug to tension torsion springs

Winding Sleeve: See Winding Plug

Window Lite: See Vision Lite

Winds On Spring: The number of winding turns on a torsion spring

Wire Glass: Glass into which wire netting is woven prevent splintering from heat or impact

Wire Rope: See Aircraft-Type Cable

Wire Size: The diameter of the wire in a spring

Wood Anchor Pad: See Spring Pad

Wood Casing: See Wood Jamb

Wood Grain: Direction or orientation of the wood, as seen in a piece of lumber

Wood Jamb: Upright wood piece forming the side of an opening

Wood Jamb Mounted: Refers to mounting vertical track to wood jambs

Woodruff Key: Special half-moon shaped steel key

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