Door Terminology

A

Acoustics - The science of sound and sound control.
Adhesive - A substance capable of holding material together by surface attachment commonly referred to as glue.
Aesthetics - The appreciation of beauty or good taste.
Aluminum - A light metal used for window frames and sashes.
Architectural Door - Doors designed for commercial and industrial applications meeting specific standards of construction (eg. Fire rating, sound transmission). Generally used to signify higher standards than “residential” doors.
Architectural Style - The characteristic form and detail of buildings from a particular historical period or school of architecture. Some examples include Colonial, Contemporary, Craftsman, Old World and Victorian styles.
Astragal - A special molding attached to one of a pair of doors that prevents them from swinging or sliding completely through the opening. Also to prevent air infiltration.

B

Back Door - An entry door typically found in the rear of a home or building.
Balloon Frame - Wood frame construction that carries the stud to the full height of the exterior wall.
Base Block - See Plinth Block.
Base Moulding - A moulding applied where the floor and wall meet, forming a visual foundation. A base protects walls from kicks, bumps, furniture, and cleaning tools. A base may be referred to as one, two, or three member. The base shoe and base cap are used to conceal uneven floor and wall junctions. Also when a relatively small moulding is applied to the top of the base with a two-member base it forms a three member base.
Bevel - To cut to an angle other than a right angle, such as the edge of a board or door.
Bifold - A door capable of being folded into two parts, as with doors that are hinged together.
Blind Mortise-and-Tenon Joint - A joint where the tenon does not extend through the mortise (a rectangular cavity in a piece of wood, stone, or other material) and does not remain visible once the joint is completed.
Book Size - Height and width of a door prior to prefitting.
Bottom Plate - See Sole.
Bottom Rail - The lower most horizontal member of a sash, door, blind or other panel assembly.
Brace Applied - to an assembled window unit to maintain its squareness. Also see Angle Brace.
Braced Frame - See Platform.
Building Code - See Code.
Butt - A door hinge, one leaf being mortised or routed into the door frame jamb and the other into the edge of the door. This is incorrectly called a “butt hinge” as the term “hinge” is usually applied to one which is attached to the surface of a door rather than to its edge such as a strap or T-hinge. A butt consists of the round central part (knuckle), flat portions (leaves or flaps), and the “pin” which is inserted into the knuckle. A pin can be a loose pin butt (removable) or fast (non-removable).
Butt Joint - A joint formed by square edge surfaces (ends, edges, faces) coming together. Also known as an end butt joint, edge butt joint.
By-Pass Door Frame - An interior door frame to accommodate two or more sliding doors that slide by each other in a horizontal direction.
By-Pass Sliding Door - One of two or more sliding doors that by-passes another door(s) in a door opening in a horizontal direction. A complete unit for such a door can be obtained consisting of two side jambs, header assembly with door track attached and necessary hardwood for hanging doors (doors may or may not be included); conserves space due to the exclusion of a required swing space.

C

Caming - Caming is the rolled formed metal banding that joins individual pieces of glass together in a decorative glass panel.
Casing - Molding of varying widths and thicknesses used to trim out interior or exterior door openings.
Cavetto - A simple concave moulding, also called a “cove”.
Checking and Splitting - Checking occurs when the wood or veneers separate horizontally to the grain. Splitting occurs when there is a break vertically with the grain.
Chevron Slat - A “V” shaped slat which assures maximum privacy and ventilation. Clad To sheathe or cover (a metal) with a metal. To cover with a protective or insulating layer of other material.
Code - Code refers to a collection of laws, regulations, ordinances, or statutory requirements adopted by governmental legislative authorities.
Cold Press - A bonding operation in which an assembly is subjected to pressure without the application of heat.
Colonial - Also called Colonial Georgian, Colonial characterizes the style of domestic architecture in America from the earliest colonies until the Neoclassical architectural period. It is sometimes separated into three periods, (1) Early American Colonial 1630-1700 (2) Georgian 1700-1790 and (3) Post-Colonial 1790-1820.
Combustible - The ability to be consumed by fire.
Concave - Hollowed or rounded inward like the inside of a bowl.
Condensation - Water vapor deposit from the air on any cold surface whose temperature is below the dew point, such as a window glass or frame that is exposed to cold outdoor air.
Conduction - The transfer of heat through matter, whether solid, liquid, or gas.
Convection - A transfer of heat through a liquid or gas when that medium hits against a solid surface.
Convex - Curving or bulging outward (the opposite of concave).
Cope - To cut or shape the end of a moulded wood member so that it will cover and fit the contour of the wall or other moulding.
Coping - Cutting the moulding to fit the pattern.
Corner Blocks, Moulded - Square blocks used in lieu of mitering the side and head casing. Also known as “turns the corner” for door and window casing.
Cove - A moulding with a concave profile used at corners particularly as a ceiling cornice. Small coves may be used as inside corner guard.
Cove and Bead - A moulding profile consisting of a ‘cove’ and a ‘bead’. Also referred to as glass bead or stop.
Cross Rail - Center most horizontal member.
Crossband - In 5-ply construction the layer of wood between the core and the face.
Crossbuck - The panels of a door separated by intersecting diagonal rails and so arranged to simulate a sawhorse, especially one with the legs projecting above the cross bar in an arrangement of panels similar to the Roman numeral ‘X’. Also referred to as a sawbuck.
Crossettes - Projecting “ears” formed by the casing at the top corners in a side of door trim which were popular during the Georgian period.
Curtain Wall - A wall, usually non-bearing, between piers or columns.

D

Dado and Lip Joint - See Rabbet Joint.
Dado Joint - Also referred to as a housed joint, it is a rectangular groove across the grain of a wood member into which the end of the joining member is inserted. Variations include “dado and tenon” and “stopped dado” joints.
Dado Tongue - See Rabbet Joint.
Department of Housing and Urban Development, (HUD) - A U.S. federal government organization whose mission is to increase homeownership, support community development and increase access to affordable housing free from discrimination. For more information go to:http://www.hud.gov/.
Diagonal Rail - A diagonal rail of a crossbuck or sawbuck of a panel or sash door. See Crossbuck.
Door Bevel - An angled cut on the lock side of a door, usually 3 degrees, that enables it to swing free of the door frame when opening and closing.
Door Core - A core placed inside the door to provide either strength or fire rating. Core types are corrugated honeycomb paper, particleboard, wood stave, mineral fiber, polyurethane, or polystyrene.
Door Face - The wide flat surface of a door.
Door Frame - A complete door frame consists of one header and two jamb legs. A strip of wood called a “stop” keeps the door from swinging through the frame. Stops are available rabbetted (Built-in) or Stitched (applied separately with staples).
Door Height - The vertical measurement of the door ranging from 6 feet, 6 inches to 7 or 8 feet.
Door Jamb - The part of a door frame which surrounds and contacts the edges of the stiles and top rail of a door. Jambs may be classified as (1) “head’ or “side” jambs and (2) “plain” or “rabbeted”.
Door Panel - A sheet of thin lumber, plywood or composition material inserted into the frame formed by the stiles, rails and mullions of a door.
Door Rails - Doors can be manufactured with double rails on the top and/or bottom so the door can be field-trimmed for off-square replacement installations.
Door Skin - The front or face panel (usually two or more plies) of a flush door. Double Action Door - A door, usually interior, with special hinges or pivots which allow the door to function in both directions.
Dove Tail Joint - A joint formed by inserting a projecting wedge-shaped member (dovetail tenon) into a correspondingly shaped cut-out member (dovetail mortise). A variation is the “dovetailed dado”.
Doweled Edge Joint - See Dowelled Joint.
Dowelled Joint - A joint using dowels or small rounded pegs of wood inserted into a hole of the same diameter (doweled construction). Also known as a dowelled edge joint.
Dowels - A wood peg or pin used to strengthen a wood joint. Drip Cap A moulding to direct water away from a non-masonry-faced structure so as to prevent seepage under the exterior facing material.
Drip caps - are usually used over window and exterior door frames and sometimes around the perimeter of the structure immediately above the foundation wall.
Dutch Doors - A door usually exterior, with an upper and lower section that can be opened separately.

E

Eased Edge - A corner rounded or shaped to a slight radius to lessen splintering and paint failure. It is not machined from an appearance standpoint, as in ‘round edge’, but rather from a utility standpoint.
Edge Joint - A joint made by bonding two pieces of wood together edge to edge, commonly by gluing. The joints may be made by gluing two squared edges as in a plain edge joint or by using machined joints of various kinds, such as tongued-and-grooved joints.
Edge Veneers - Doors can be manufactured with vertical edge veneers such as oak or birch to match the veneer on the face of the door.
End Joint - A joint formed by the ends of wood members. The most common is the “fingerjoint”.
Entry Door - A door typically found in the front of a home or building. Environmental Condition - The state of the environment necessary for the support and comfort of the inhabitants. The control of air quality, light, temperature, food, security, etc.
Extension Jamb - Flat parts which are nailed to the inside edges of the window or door frame, so that it will fit a wider wall.
Exterior Threshold - A threshold non-symmetrically beveled, (the more gradual and longer bevel facing the exterior) which, when secured to the exterior door frame sill and/or finished floor, prevents water from driving under the door.

F

Façade - The main or front elevation of a building.
Face - Outer or exposed ply in cross banded construction. Also the surface from which lumber grade is determined.
Face Panel - See Door Skin.
Facing - A protective covering that protects the outside of a building.
Fascia - A wood member, surfaced four sides, used for the outer face of a “box cornice” where it is nailed to the ends of the rafters and “lookouts”. Sometimes refers to the “face” of a mantel.
Fenestration - The placement or arrangement and sizes of the windows and exterior doors of a building.
Fiberglass - The most familiar type of insulation. It is spun from molten glass, and is pure white. Additives and binders often color the fiberglass, with pink and yellow being the most common. Fiberglass comes in rolls, batts and as loose insulation which is blown into place.
Finger Jointing - A method of joining wood pieces milled in the shape of fingers, which mesh together and are held firmly in position by a water-resistant adhesive. This method has enabled the millwork industry to create longer lengths of wood and to utilize shorter pieces of raw material. Finger jointing is not a new woodworking technique but has been vastly refined. So precise can the joint now be made on such items as mouldings, door and window jambs, and doors that the lines of joining are barely perceptible. When there is no great variation in grain or color, the end-welded pieces appear as one.
Fire Door Fire - doors are designed to meet independent testing facilities’ (Underwriter’s Laboratory [UL] and Warnock Hersey [WH] standards for fire ratings of 20, 30, 45, 60, or 90 minutes. The specific rating is achieved through the application of special door cores and framing materials. Fire Resistant Ability of a material to resist catching on fire when exposed to a flame, typically for 10 to 20 minutes.
Fireproof Construction - Construction designed to withstand a complete burnout of the contents for which the structure was intended without impairment of structural integrity.
Flashing - A metal or plastic strip used to prevent water and air leakage between the window or door frame and the surrounding wall. It is attached to the outside face of the head jamb and side jambs.
Flat Jamb - This jamb is a plain piece of lumber, not rabbeted or ploughed. Instead of a door rabbet, this jamb requires a door stop applied to prevent the door from swinging through.
Flat Sliced - Veneers cut from a half log that produces a light variegated grain similar to sawn lumber.
Flexible Sweep - A rubber or vinyl strip that easily bends and is applied to the bottom of a door to create an effective seal against the sill (threshold).
Flitch - A complete bundle of thin veneer sheets laid together in sequence as they are cut from a given log or section of a log.
Flush Door - A flat-faced door that may have a variety of door facings and may be hollow-core or solid-core.
Folding Door - One of two or more sliding doors hinged to move laterally in an opening. Also known as an accordion door. A complete unit may consist of doors with butts applied, track and guide hardware, door pulls and door frame (optional). Frame - Parts which enclose the window or door sash. They are attached to the wood members lining the rough opening. Vertical frame members are called ‘side jambs’; the top, horizontal piece is the ‘head jamb’; the bottom, horizontal piece is the ‘sill’.
Frame Wall - See wood frame wall.
French Door - An interior or exterior door consisting of stiles, top and bottom rail and divided glass panels or lights. Often used in pairs and can be referred to as casement or terrace doors.
Front Door - A door typically found in the front of a home or building.
Fungi - Low parasitic forms of plant life which deteriorate wood by using it as a source of food and may be wood staining or wood destroying.
Furring - Narrow strips of wood spaced to form a nailing base for another surface. furring is used to level to form an air space between the two surfaces especially in damp situations and to give a thicker appearance to the base surface.

G

Gap - Open splits in the inner ply or plies or improperly joined veneer when joined veneers are used for inner plies.
Gothic Head - An entrance or door head in the form of a pointed arch.
Grade - A quality standard applied to a millwork product to distinguish one from another. Also a level or elevation of a land or water surface. Average grade is the arithmetic means of the elevations of various ground surfaces within a stated area of building construction. Finished grade is the surface elevation of lawns, walks, drives, or other improved surfaces after completion of construction or grading operations. Natural grade is the elevation of the original or undisturbed surface of the ground. Sub-grade is the ground elevation established to receive an additional surfacing.
Grade Door - Service door derives its name from usual installation of door at grade (the level of the ground at the building).
Groove - See Plough.
Groove and Rabbet Joint - Rabbet Joint where the groove substitutes for the dado.
Gypsum - A type of rock that provides excellent fire protection. Natural crystalline calcium sulfate used as an extender pigment in paint, and in the manufacture of gypsum wallboard and plaster of paris.
Gypsum Dry Wall Plaster Interior Finish - See Sheet Rock. Also see Gypsum Board.

H

Half-and-Half House - A house built with a combination of wood frame and masonry exterior walls, with the first level being masonry while the second is wood frame.
Hanging Stile - A door stile to which the butts or hinges are applied. They can be referred to as hinge stile. Hanging stiles also refer to the side jamb of a window or sash to which pulleys, balances or hinges are applied.
Hardboard - A generic term for a panel manufactured primarily from interfelted lignocellulosic fibers (usually wood), consolidated under heat and pressure in a hot press to a density of 496 kg/m3 (31 lb/ft3) or greater and to which other materials may have been added during manufacture to improve certain properties. Haunched Mortise-and-Tenon Joint - A mortise and tenon joint in which the tenon is not the same width as its wood member.
Head Casing - The horizontal casing across the top of the window or door opening.
Heat Loss - The heat transmission rate multiplied by the area of the door. Hinge Jamb Side jamb in which the door hinges (butts) are applied.
Hinge Stile - Refers to the side jamb of a window or sash to which pulleys, balances or hinges are applied.
Hinged Door - An exterior or interior door hung by attaching butts to the stile so that the door swings on a vertical axis. These doors may be single (swinging thru 90 degrees) or double-acting (swinging thru 180 degrees). Double-acting doors do not require a door stop.
Hinged Interior Wood Door Units - See pre-hung door.
Hip Raised Door Panel - A raised door panel with the edges of the raised face perpendicular.
Hollow Core Door - A type of door that has corrugated cardboard between the stiles and rails and is made up of an interior frame of stiles and rails, covered by a skin of veneer or hardboard, plastic, or metal.
Horn - The extension of a stile jamb or sill.
Housed Joint - See Dado Joint.

I

Infiltration - Heat loss due to cold air filtering through cracks or spaces around an exterior door.
Insulated Cavity Type Wall - A wall that is constructed of a framework of wood or steel and has some form of insulation added between the framework to improve the energy efficiency of the wall.
Insulation - Prevention of the passage or leakage of heat, moisture, sound, or electricity.
Interior Door Frames - A door frame installed in the interior wall of a structure. Intermediate Rail - Horizontal member of a door located between the top and bottom rails.
In-The-Wall Frame - See Pocket-Type Door Frame. Irregular Head Door Frame Door frame for a non-rectangular opening. The head may be circular elliptical, Gothic, segment, peak or rake.

J

Jack Stud - Vertical wood member at each side of the rough opening for a window or door and supports the header.
Jamb - The top and two sides of a door or window frame which contact the door or sash: top jamb and side jambs. The most common size for interior use is 11/16” thick by 4-9/16” wide.
Joist - Heavy pieces of lumber, steel, or other built-up material laid on edge horizontally to form the floor and ceiling support system.

Knob Latch Set - Door hardware for keeping a door closed and with a spring-operated latch bolt activated by a knob. Also known as a passage set.

L

Latch Set -See Knob Latch Set.
Laying Panels - Grain of panel running horizontally.
Lock Block - A concealed block of wood or particleboard glued inside a door. When installing a lockset, a hole is drilled through the door faces and the lock block. It provides support for the lockset.
Lock Rail - The intermediate rail of a door at lock height.
Louvre (or Louver) Door - A door, bifold or shutter constructed with a series of downward-sloping, horizontal slats that allow ventilation, inhibit sunlight, and provide some privacy.
Lug - An extension of the stiles beyond the meeting rails of a sash, usually ogee-shaped and sawed ornamentally on the inside of the stile. Sometimes referred to as an ogee lug. Also the interior door side jamb extension beyond the dado is called the lug. Can also be termed joggles. See Horn.

M

Masonry Wall - A wall consisting of clay, shale, concrete, gypsum, stone or other similar non-wood materials bonded together with mortar; the masonry units may be hollow or solid.
Mechanical Wear - Continual physical contact with a material that eventually decreases its function, e.g. a stair tread.
Medallion - A raised decorative wood design sometimes used on flush doors. Medium Density Fiberboard (MDF) - The generic name for a panel manufactured from wood fibers combined with a synthetic resin or other suitable binder and bonded together by applying heat and pressure in a press. It is available in different densities and can be used for door core, door stiles or door rails.
Mesh - The number of meshes or open spaces per lineal inch in width and height in insect wire screening.
Mineral Core - Fire-rated core of a door available in 45, 60, or 90 minute versions. Miter Joint - The joining of two members at an angle that bisects the angle of junction.
Monotony - Uniformity or lack of variation.
Mortar Joint - A joint in a masonry wall created with a mixture of cement materials, fine aggregate, and water, to bond masonry units such as brick or cinder block together.
Mortise-and-Tenon - A joint formed by the end of one member being inserted into the mortise of the other member; the tenon may be secured in the joint by means of steel pins or nails (pinned mortise and tenon).
Mullion - The upright or vertical member dividing the panels in a door. A mullion is also the vertical member of a sash, window or door frame between openings in a multiple opening frame. The mullion is known as the ‘mullion center’. Frames are termed ‘mullions’, ‘’triples’, or ‘quadruples’, depending on whether they have one, two or three mullions respectively. In door they are sometimes referred to as ‘muntings’.
Muntin - A short bar, horizontal or vertical extending from a bar to a stile, rail or other bar.

N

Nominal Size - As applied to timber or lumber, the size which it is known and sold in the market (often differs from the actual physical size).
Nominal Thickness - The size by which it is known and sold in the industry (often differs from actual or physical thickness).

O

Obsolescence - Being in the process of passing out of use or usefulness; becoming obsolete.
Open Mortise-and-Tenon Joint - See Slotted Mortise-and-Tenon.
Ovolo - A convex profile, usually a quarter section of a circle and similar to the profile of ‘quarter round’.

P

Panel - A wood surface within a surrounding frame. All panels have structural frames, the interstices of which are filled with sheets or fields called panels. The frame is necessary for adequate strength only with the panels occupying considerable more area than the frame. The panel may be raised above or recessed below the surrounding frame and set off from it by moulding or other decorative treatment. Panel also refers to a sheet of plywood or thin plywood. Particleboard - A formed panel consisting of particles of wood flakes and shavings, bonded together with a synthetic resin or other added binder. The particles are classified by sizes, dried to a uniform moisture content, mixed with binder, mat-formed, compressed to density, and then cured under controlled heat and pressure. Particleboard can be used to create a solid-core door.
Patio Door - See Terrace and French Door.
Pediment - A low-pitched triangular entrance head or cap. Also described as a triangle formed by sloping roof and horizontal cornice. May apply to window and door openings.
Permanency - Durable and has long-lasting qualities. The property of being able to exist for an indefinite duration.
Pitch - Accumulation of resin in the wood cells in a more or less irregular patch. Plank and Beam - A type of construction technique where planks and beams (large timbers) are utilized in a framework to provide the support structure for a house or building.
Plank Door - A door constructed from planks. The lumber used is typically one inch or less thick and 4 to 6 inches wide.
Planted Moulding - A moulding applied to a surface and projects or remains above it. Also known as a raised moulding, as opposed to a solid sticking or applied moulding.
Platform - Wood frame construction that terminates the stud at each level. Also referred to as a western frame, repeat story frame or braced frame construction. Plies - The plural of Ply.
Plinth Block - A square block at the base of a pilaster of a block of wood placed at the bottom of side door casing to terminate the casing as well as the base. Since the door casings and bases are moulded, plinth blocks offer a sturdier member and a better appearance. Plinth blocks are thicker and wider than the abutting members; also base block, foot block or pilaster base.
Plough - A rectangular groove or slot of three surfaces cut parallel or with the grain of a wood member, in contrast to “dado” which is cut across the grain. Plow See Plough.
Plug - Sound wood of various shapes for replacing defective wood portions which have been removed. They are usually held in veneer by friction only until veneers are bonded into plywood. They can also be synthetic made of fiber and resin aggregate used to fill openings and provide a smooth, level, durable surface. Plumb - Exactly perpendicular or vertical. Or, at right angles to the horizon or floor. Ply - Refers to the number of veneers to make a plywood skin. The outside plies are called the "face" and the "back," and the center plies are called the "core." Plywood - A crossbanded assembly of layers of veneer or veneer in combination with a lumber core or plies which are joined with an adhesive. The grain of the adjoining veneer or plies is approximately at right angles. An odd number of plies is generally used. Two types of plywood are recognized, “veneer plywood” (layers of veneers only) and “lumber core plywood” (lumber core with veneers or plies bonded to it).
Pocket - A removable section of a pulley stile (side jamb) of a box window frame (pocket and pulley) which gives access to the weight box. The standard width is roughly 2"- 2-1/2'’ with the height determined by the length of the sash weight. The lower end of the pocket is located about 6" above the window sill and may extend midway to the meeting rail. Also referred to as a weight access pocket or weight pocket.
Pocket-Sliding Frame - See Pocket-Type Door Frame.
Pocket-Type Door Frame - An interior door frame to accommodate a door that slides into a partition pocket-type door frames which are often sold as a unit consisting of an outside jamb, header assembly with door track attached, split jamb pocket assembly and hardware for a hanging door.
Prefit - Trimming additional width or height off the nominal size of a door to make it fit in the frame better.
Prehung Door Unit - A pre-cut and assembled unit consisting of a wood door with preparation for lock hardware that is hung on hinges in a wood frame. The wood frame includes the one or two piece jamb adjustable or as-ordered width as well as the door stop mouldings and casings (trim). Door units other than conventionally hinged are also available.

Q

Quarter Sliced - Veneers cut from a quarter log or a flitch.

R

Rabbet - A rectangular cut consisting of two surfaces cut on the edge of a member parallel with the grain. A rabbet has two surfaces and a “plough” has three. Also referred to as a “rebate” or rabbit.
Rabbet Joint - A joint formed by the rabbet(s) on one or both members. Also referred to as a rabbeted edge joint or rabbeted right angle joint.
Rail - The cross or horizontal pieces of a door’s framework of: "top rail," "mullion rail," "lock rail," and "bottom rail" are different types of rails based on their location in the structure of the door.
Raised Panel Door - A door using a compressed hardboard (Masonite) door facing that has been hydraulically pressed to create a simulated raised panel design. It may have a smooth or textured wood grain finish with either a hollow-core or solid-core.
Reveal - The margin visible between the window or door sash and the surrounding frame.
Rift Cut - a veneer produced from a quarter log which shows an accentuated vertical grain.
Ribbon Stripe - A veneer figure which consists of alternate light and dark stripes running primarily the length of the veneer and produced by quarter sawing.
Right Angle Joints - A 90 degree joint formed by end to face, edge to face or edge to end of wood members; the joint may be formed with the grain, at right angles or parallel to it.
Rim Type Door - A door with a framework only on the edges of the door. The basic design of screen doors is a rim type frame with screening. Horizontal and vertical cross members are used to stiffen the screening material.
Rotary Cut - a veneer cut from a full log--like unwinding a roll of paper--which produces a wide and variegated grain pattern.
Rotary Cut Face Veneer - Veneer cut on a lathe which rotates a log or bolt against a broad cutting knife. The veneer is cut in a continuous sheet much the same as paper is unwound from a roll.
Rough Opening - Refers to the finished, cut-out opening into which a door and frame will be fitted.
Rounded - See Eased Edge.

S

Saddle - See Threshold.
Safety Tempered Glass - Masonite glass is safety tempered making it stronger than standard glass through a controlled thermal process to increase strength and change the break pattern into small pieces.
Sawbuck - See Crossbuck.
Scarf Joint - An end joint formed by having the two ends of the members beveled to form sloping plane surfaces.
Screen Door - A door usually occupying the exterior rabbet of an exterior door frame whose purpose is to keep out insects by means of insect wire screening while admitting the maximum amount of air.
Screening - A mesh of fine aluminum, galvanized steel or bronze wire often referred to as ‘insect wire screening’, ‘wire cloth’ or ‘insect wire’.
Sheathing - A surface, usually of wood or fiberboard, applied to the exterior faces of the studs or wall frame.
Shouldered Rabbet Joint - See Lap Joint.
Sidelite - An assembly of stiles and rails, with or without a wood panel containing a single row of glass panels or lights. Installed on one or both sides of an exterior door frame, especially a front entrance door frame. Sidelights provides light, especially for an entry hall, as well as decorative appeal.
Sill - A lower horizontal member of a window or sliding door frame.
Skid Block - A small wood or metal block applied to the bottom edge of a ‘prefit door’ in order to prevent damage. Referred to as a ‘scuff strip’.
Skin - See Door Skin.
Slat - A thin narrow strip of wood used in door and window blinds, doors, transoms and louvers.
Sliding Door - A door which slides in a horizontal direction parallel to a wall of the structure. They may be of the ‘pocket’ or ‘in-the-wall’, ‘folding’ ‘accordion’ or the ‘by-pass’ type.
Sliding Door, Pocket-Type - A door which slides horizontally into a wall pocket or slot recessed into the wall of a structure imparts additional space to a room compared to the conventionally-hinged door since no swing space is required. See Door Frame (pocket-type door frame).
Slotted Mortise-and-Tenon - A mortise and tenon right angle joint in which the tenon is visible on two edges once the joint is completed. Also known as a bridle” or “slip” joint.
Solid Composition Panel - Panels made from finely granulated wood bonded with thermosetting resins of the phenol formaldehyde type. They may be either flat with a sanded thickness of ¼ of an inch or have a greater thickness and be raised.
Solid-Core Door - A door with a solid interior made from composite wood, agri-fiber, wood staves, particleboard, or fire-rated mineral fiber.
Solid Sticking - A mould or profile worked on the article itself. Also referred to as ‘solid stuck’.
Solid Stuck - See Solid Sticking.
Solid-Core Flush Door - A flush door consisting of a core of solid wood blocks or strips with cross banding and face veneers or face veneers only.
Sound Knot - Solid across its face, as hard as the surrounding wood, shows no indication of decay and may vary in color from natural color of the wood to reddish brown or black.
Spacer Block - A thin strip of wood placed on the edges of a pre-hung door to take up the door clearance while in transit; also spacer wafer.
Spacer Wafers - See Spacer Block. Spline Joint - A joint formed by the use of a “spline”. Also known as a “slip tongue” joint.
Split Jamb - This interior or exterior jamb is composed of two halves that fit together. One side has a built-in stop and the other side can slide in or out to adjust the frame for various wall thicknesses, usually from 1" to 2".
Square Cut - See Butt Joint.
Sticking - See Solid Sticking.
Stile - The upright or vertical framework pieces of a door.
Stop - A moulding primarily used in window and door trim that is positioned to stop the door or window sash from opening beyond a set point.
Storm Door - A panel or sash door occupying the exterior door frame to provide protection from cold weather.
Storm Panel - An exterior covering, door, shutter, or sash to protect the window during a storm.
Straddle Moulding - A two member decorative glass bead-like moulding around the light opening of a flush door.
Strike Jamb - Jamb opposite the hinge jamb. A jamb on which the lock or passage-set strike plate is installed.
Strike Jamb - A jamb opposite the hinge jamb or a jamb on which the lock or passage-set strike plate is installed.
Strike Plate - A metal piece mortised into or fastened to the face of a door frame side jamb to receive the latch or dead bolt when the door is closed.
Striking Stile - The door stile containing the lock.
Stub Tenon-and-Mortise Joint - See Blind Mortise and Tenon Joint.
Stucco - An exterior covering for walls created with a combination of sand, cement, and water and consists primarily of lime and aggregate in a Portland cement base applied onto a metal lath or wire fabric (woven or welded).
Sub-Jamb - A jamb-like member, usually surfaced four sides, which increases or extends the width of the exterior door frame jamb. Sub-jambs imply a larger width than “jamb liners”. Sub-jambs can also be used with window units. Also known as an extension jamb.
Sunburst - A semi-elliptical area, the lower center of which contains a sun-like figure with radiating sun rays. It closely approaches the sudden appearance of sunlight as seen through a break in the clouds. It may consist of wood panel or glazed sash, the bars simulating the sun’s rays. It is sometimes called, ‘elliptical head’ or ‘fanlight’.
Sunroom - A glass enclosed porch or living room with a sunny exposure. Also called a sun porch or sun parlor.
Sweep - A rubber or vinyl strip applied to the bottom of a door to create an effective seal against the sill (threshold).

T

Telegraphing -When the internal components of a door show through as lines on the face of the veneer.
Tenons - A projecting tongue-like part of a wood member to be inserted into a slot (mortise) of another member to form a “mortise and tenon joint”.
Terrace Door - Exterior door, usually generous of glass, opening on the patio or terrace.
The Threshold Sill - A door sill with the threshold worked on it.
Threshold - A wood or aluminum member, beveled or tapered on each side, and used with exterior or interior door frames. Classified as ‘interior’ or ‘exterior’ or ‘saddle’.
Toenail - To drive a nail diagonally to the surface of a vertical member to fasten it to a horizontal member. This is usually done when end nailing is not practical.
Tongue Shoulder Joint - See Rabbet Joint.
Tongue-and-Groove Joint - A joint formed by the insertion of the “tongue” of one wood member into the “groove” of the other; modifications include tongue and groove rabbet joint, dado tongue and rabbet, tongued shoulder joint, dado and rabbet joint, dado and lip joint.
Tongue-and-Groove Rabbeted Joint - See Rabbet Joint.
Top Rail - Upper most horizontal member of a sash, door, blind or other similar panel assembly.
Transom - A horizontal member separating a door from a window panel above the door, or separating one window above another.
Transom Sash - A sash installed in a “transom”.
Trim - Millwork, primarily mouldings and/or trim to finish-off (trim around) window and door openings, fireplaces, walls and other members.
Trimming Out - Installing “trim,” sometimes referred to as interior finish.

U

U Value - The rate of heat loss is indicated in terms of the U-value of a window assembly. U-value ratings generally fall between 0.20 and 1.20. The insulating value is indicated by the R-value which is the inverse of the U-value. The lower the U-value, the greater a window's resistance to heat flow and the better its insulating value. See Heat Transmission Coefficient.
Upright Panel - Grain of panel running vertically.

V

Veneer - A thin sheet or layer of wood, usually rotary cut, sliced or sawn from a log, bolt or flitch; thickness may vary from 1/100 to 1/4 of an inch. Also referred to as skin, ply, veneer ply.
Void - An empty area or open space.

W

Warranty - A statement or representation that the goods and/or services will perform as promised.
Weathering - The mechanical or chemical disintegration and discoloration of the surface of wood caused by exposure to light. The action of dust and sand carried by winds and alternate shrinking and swelling of the surface fibers with continual variation in moisture content due to changes in the weather. Also an inclined surface on a member such as a cornice or sill which directs away rain water.
Weatherstrip - Variously shaped metal, vinyl plastic or moulded fiber strips which fit tightly against sash or door frame parts to prevent air infiltration through cracks. Adjustable pressure weatherstrip-sash or window weather-stripping on which sash tension is maintained by means of spring action.
Wood Frame Wall - A wall basically framed or constructed of wood members. Wood members used are studs, plates and sheathing; may be faced on the exterior with wood or non-wood facing materials such as brick, stucco and stone. Also referred to as a “frame wall”.
Wood Stave Core - This wood core is made by bonding together small pieces of solid wood to form a core blank. Once bonded, it is sanded to a uniform thickness.

X

X-Ray Doors - Doors that are manufactured with a lead insert and are designed to block the transmission of x-rays.