Glossary of Terms

Glossary of Door Terms

Here are some handy definitions of terms you may encounter while buying or installing a Caldwell’s door.

ActiveIn paired doors, the hinged door leaf which is primarily operable.

Affidavit LabelA label that is placed on a fire-rated door in that a manufacturer states that the door meets certain test criteria.

Air InfiltrationAir passing through a door unit when the door is under pressure, usually from wind.

Annealed GlassGlass which has been heat strengthened or tempered.

AstragalA wood or aluminum 'post' attached on the latch-side edge of one of a set of paired or double doors, which covers the space between doors when they are closed. Which acts like a stop for the active door.

BacksetRecess- or spacing, for locating a machined hole. The distance from an edge or surface to the center or edge of the recess.

Ball-Bearing HingeA heavier-duty hinge than the standard hinge, with bearings supporting the pivots. Ball-bearing hinges are usually used for heavy doors that will be in commercial or industrial use.

Ball CatchA spring-loaded ball mechanism that is inserted into the top edge of doors that have dummy locks. The ball engages a plate on the header that has a dimple to receive the ball, which in turn keeps the door closed.

BootA term used for the rubber part at the bottom or top end of an astragal, which beds the astragal end and seals between the end and the door frame or sill.

Boss, Screw BossA part that enables the fastening of a screw into the feature, thereby allowing assembly of the part with another. Screw bosses are common features of molded plastic lite frames and extruded aluminum doorsills.

Box-FramedIn door and sidelite assemblies, a term used to differentiate door and sidelite units which are first framed as separate units. Box-framed doors are joined to box-framed sidelites.

BradA small nail with a small head, usually used to fasten small trim and moldings, also known as a finish nail.

BrickmoldA molding- type of door casing. Used to trim the outside edge of an exterior door frame.

BuckA term usually used in masonry construction to describe a door frame or a sub-frame in a masonry opening, around which a steel door frame wraps and is fastened.

ButtButt hinges are often referred to simply as butts.

Carpet ShimA spacer block used under a doorsill to raise the sill an appropriate amount if carpet is used, so the door clears the carpet when opened.

CasingA horizontal or vertical molding, which accents or trims edges of doors and windows to the surrounding walls.

CaulkingSealant, used to seal against air and water leakage through the joint or recess.

CladFacing or jacket which works as a protection against weather and provides a finished appearance. Cladding may be painted metal, plastic, or a heavy coating applied by the manufacturer.

Clear JambsNatural wood door frames, without paint or primer applied, and which appears to be made of full-length pieces of stock, without joints or knots.

Closed-Cell FoamSponge-like material, usually used in gaskets and weather-stripping which compresses into joints, but absorbs little water.

Closer BlockAn inside reinforcement, usually placed across the top edge of a door, to enable firm fastening of self-closing hardware.

Continuous SillA sill used for a type of door and sidelite unit in which the unit has full-width top and bottom frame parts, and an internal post(s) separating sidelites from the door.

Corner Plug, Corner Seal PadA small part, usually made of resilient material used to keep water from getting between the door edge and the jambs, adjacent to the bottom gasket.

Cove MoldingMolded piece of wood with concave profile used where doors meet a wall, or frame.

Cross-boreA large through-hole, near the edge of a door panel, which houses a cylinder lock-set or deadbolt latch.

Cylinder LockLock hardware that mounts into a door which has been prepared with a bore hole(s).

DadoA machined or sawn rectangular groove cut into a board or part so that a matching piece can be fitted into it to form a joint.

Deadbolt SpacingThe distance between the cylinder lock to the bore for the deadbolt lock.

Door HandThe door hand is the description of which way the door opens.

DoorlitePiece of Glass within door, used as a panel(s).

Double-GlazedInsulated glass- two panes of glass separated with a sealed airspace between.

Drip StripIn exterior doors, a fitting used across the outside face of the door adjacent to the bottom edge. It is used to divert cascading rain away from the door bottom edge and away from the door/sill joint.

Drywall OpeningA rectangular opening in a wall, usually an interior wall, prepared to the size necessary to receive a pre-hung door assembly.

Dummy CylinderA lock without a latch, typically used for the passive door panel of a double door unit, so that the hardware appears equal to that used on the active panel.

Electric StrikeA mechanism, which allows a switch to open the latch of a door.

End Seal PadA closed-cell foam piece, about 1/16-inch thick, in the shape of a sill profile, fastened between the sill and the jamb to seal the joint.

EscutcheonA stamped decorative plate. Used to trim the shaft of a door knob, deadbolt latch or the opening where the shaft or latch adjoins the face of a door.

FaceplateThe plated or solid metal trim piece, that is housed flush into the edge of a door.

Faceplate MortiseThe pocket in the edge of the door that is mortised to the door. Highly secure.

Finger JointA way of joining short sections of board stock together, end to end to make longer stock.

Fire DoorA door which has been tested to contain the spread of fire from one room or occupancy area to another. Fire doors are listed and labeled to show their ratings in terms of time.

Flush-GlazedA type of glazed door which has its glass perimeter moldings flush with or set down from the face of the surrounding door.

FoamRigid foam is used as the insulating and binding core for doors. Flexible foam is sometimes used as a gasket around door openings.

Foot BoltA steel pin housed in a bottom edge of door or astragal with a latch mechanism, which can be driven down into a receiver socket or hole in the floor or threshold. It allows the door to be better secured when closed.

FrameThe perimeter to which the door is hinged and latched. See jamb.

GlazingThe elastic material used to seal glass to a surrounding frame.

GrilleA removable face-mounted assembly of thin wood or plastic pieces, which when in place, gives the lite or insert a patterned multi-pane look.

Grooved GlassGlass, which has been decorated with abrasively routed recesses.

HandingA term, which describes or determines the direction of swing of a door when opening.

Head BoltA steel pin housed in a door top edge or astragal. See foot bolt.

Head, Head JambThe horizontal top frame member of a door assembly.

Header ClearanceThe clearance between the top edge of the door and the head jamb.

HingeAn assembly of metal plates and a cylindrical metal pin, which when fastened to a door edge and to a doorframe, allow the door to swing or rotate in its frame.

Hinge SizesThe distance across the hinge, measured parallel to the hinge pin.

Hinge StileThe full-length vertical pane of a door, at the side or edge of the door, which fastens to its frame with hinges.

InactiveA term for a door panel fixed in its frame that is not operable.

Insulated GlassA glass assembly of multiple full-lite pieces, separated by an airspace/ perimeter spacer and sealed as a unit.

InswingWhen the hinged door panel is opened, the panel swings into the building.

JambA vertical perimeter frame of a door unit.

Jamb JackA fastener device for fixing a door frame to a wall structure which allows the space or margin between the frame and the structure opening to be varied by turning the fastener screw.

Jamb StopIn interior door frames the stop is the material attached to the jamb to which the door closes against. In exterior door-frames, it is the molded-in rebate surface of the jamb against which door panels close and seal.

KerfA thin slot cut into an exterior jamb, that weather-stripping can be inserted.

King StudIn a wood-framed rough opening, the stud which runs full height from floor plate to ceiling plate where trimmer stud attaches.

KnuckleThe feature of a hinge where the hinge leaf is cut for two or three projections which wrap and form a barrel or socket for the hinge pin.

LaminateA thin sheet of wood or plastic that is bonded with adhesive to a core or substrate which creates a decorative and usable surface.

Latch BoreThe hole drilled into the edge of a door to accept the door latch lock hardware.

LeafA term which can apply to a door or hinge and which defines a part of the assembly which can swing on a pivot. Butt hinges have two leaves.

LiteAn assembly of glass and a surrounding frame.

Lock BlockA rectangular block of wood or other solid material, placed inside a door assembly at the lock side edge, which reinforces the assembly when the lock hardware is installed.

Lock BoreFor cylindrical lock-sets, the large through hole near the door panel's lock edge into which the lock mechanism is placed and installed.

Lock HeightThe dimension from the top of the door to the center line of the lock bore.

Lock StileIn insulated door assemblies, the full-length part which makes up the lock edge of the door panel.

Low-E GlassGlass which has been factory coated with a thin layer of material which acts to absorb and reflect heat and UV rays.

MiterAn angled cut across the end of a lineal part, usually done to join with a similarly cut part at a corner. Most typically used in casing.

MortiseA recess cut into the surface or edge of a part, usually for the purpose of housing hardware such as hinges, latch plates etc.

Mortise-Type LockA lock-set, which is housed into a deep recess cut into the edge of a door.

MullA short term for mullion. Used to describe the edge-joining of two door units or sidelites together.

MullionA post or divider which runs from sill to frame top in multi-panel doors, or sidelite assemblies.

Multiple Extension UnitIn patio door assemblies, a fixed door panel in a separate frame, edge-joined to a patio door unit to add another glass panel to the installation.

MuntinsIn glazed lite assemblies, thin vertical and horizontal divider bars, which give the lite a multi-paned look. Muntins may be part of lite frames, and on the outside surface of the glass, or assembled between glass in insulated glass units.

NRP HingeAn abbreviation for a hinge with a non-removable pivot pin. NRP hinges are used when exterior doors swing out, as a security feature. The fixed pins make it impossible to remove a door by driving out pivot pins.

Open-Cell FoamA foam material which has passageways between cells. Open-cell foam will absorb and retain water.

OutswingAn exterior door assembly in which the door panel swings outside the building.

Passage LockA lock-set, which will retain a door close, but which cannot be locked.

PassiveIn a double or two-panel door assembly, the door which usually remains closed and fixed by bolts at top and bottom.

PlantA decorative molding applied to the surface of a flush door, to give the appearance of a raised-molding design.

PVCAbbreviation for polyvinyl chloride, a plastic material used to make molded or extruded parts.

R-ValueA number which describes in relative terms the ability of a material or assembly to resist the flow or transmittance of heat. Assemblies or materials with high R-values are better insulators than those with lower R-values.

Rabbet, RebateA groove or step cut along the length of the edge of a piece of wood that is to be joined to another with a corresponding tongue or ledge cut into it.

RailIn stile and rail doors, horizontal pieces at the top and bottom edges at intermediate points, connecting the stiles together.

RevealThe offset or space between edges of parts.

RiserA term which describes the part of an adjustable sill which can be moved up or down by turning adjusting screws.

Rough OpeningA structurally-framed opening in a wall for a door or window.

Safety GlassGlass which when broken, shatters into small pieces without sharp edges.

SealantElastic material pumped or trawled into a joint to prevent water penetration.

ShimA thin piece of material used between parts of an assembly to change and fix the distance between parts, when they are fastened.

SideliteA fixed narrow panel, installed next to a door panel, for decorative purposes.

Slide BoltThe part of an astragal assembly which places bolts into frame heads and sills. It is for fixing passive doors closed.

StileIn stile and rail doors, the vertical pieces on both sides that connect the rails together, enabling lock, latch and hinge mortising to be done.

StrikeA metal part with a hole or recess for receiving a door latch. It has a curved or ramped face so that a spring-loaded latch contacts it when closing.

Stile and Rail DoorsA type of door constructed without a door skin, so that the vertical and horizontal members are visible.

SubstrateThe base or core material in an assembly of parts. The full-length wood or composite part of the sill.

Tempered GlassA glass sheet, which has been strengthened by heat processing.

TemplateA pattern used to machine-cut a precise hole or recess into a door or frame part.

Thermal BreakA feature of a door/frame assembly which separates metal or glass exposed to outside temperatures from coming into contact and transmitting heat to or from inside-exposed parts.

ThresholdAnother term for sill. The horizontal part of a door assembly, fixed under the door panel and bearing on the floor.

TransomA framed glass assembly mounted atop a door assembly.

Trimmer StudIn a wood-framed rough opening, the stud or framing member which runs vertically from the sub-floor to the structural header member, into which a door frame is fastened.

Triple-GlazedAn insulated glass assembly made of three thicknesses of glass, with air spaces between.

VeneerA thin film or facing, adhesively bonded to a core or substrate, which makes up the exposed and decorative face of an assembly.

WarpA permanent curvature or deviation from straightness.

Wired GlassGlass made for use in fire doors, which has embedded wires which bind the glass, and permit the glass to remain solid when exposed to fire.