Apron
The inside trim piece that lies flat against the wall beneath the stool (interior sill extension). This is a traditional treatment usually associated only with double hung windows.
Awning Window
A window unit which projects outward toward the exterior of the building as it opens. Hinges at the top of the side frame members, permitting the sash to open up and out like an awning.
Balance (Sash Balance)
A system of cords and pulleys (block and tackle) or spring friction devices which help in raising double hung sash and keep it in any position by counter balancing the sashe's weight. This mechanical device is mounted in the jamb.
Basic Unit
This term is given to the fundamental "building block" units of each standard window product line. These units are members of a series of standard sizes. They lack exterior trim or installation flanges but are otherwise complete.
Bay Window
A window which projects outward from the exterior of a building. It is composed of three or more individual units. The center unit(s) are parallel to the exterior wall with the side or flanking units aligned at 30 degree or 45 degree angles.
Bow Window
A window projecting outward from the exterior of a building. Composed of four or more units which are aligned in a gently curving contour.
Brick Mould
A form of exterior trim (casing) for windows and doors. In addition to serving as an anchor point for installation of the unit brick mould provides a boundary for brick or other siding material on the face of the building and attachment of hardware. (Sometimes called Shake mould).
Capillary Tube
A breather tube device used in insulated glass units for pressure equalization. It consists of a long tube so small it only alows gases to pass. It keeps pressure in the sealed unit equal to uotside the unit.
Casement Window
A style of window which is hinged on the top and bottom frame members. These units are constructed so that they swing outward. (Projected window)
Check Rail
The top rail of the lower sash and the bottom rail of upper sash which meet (overlap) when a Double Hung window is closed.(also called meeting rails).
Clad
A designation given to products whose exposed exterior surfaces are sheathed with specially formed aluminum.
Cottage Window
The name of every traditional style of Double Hung window which has a lower sash which is larger than its upper counterpart.
Daylight Opening
The portion of a window or door's glazing which is actually visible. A small percentage of a unit's glass will always be concealed as it is mounted in the wood parts.
Dimensional Windows
Custom units created by reducing the size of existing standard units. Dimensional units cannot be smaller in size than the smallest standard size nor larger than the largest standard size.
Direct Set
Refers to window units which do not have sash. The glass is mounted directly into the frame. Units of this type do not operate.
Divided Lites
See"True Divided Lites"
Double Hung Window
A type of window which has two vertically sliding sashes which bypass each other in a single frame. Suspension and operation of the sash is achieved by using a block and tackle mechanism powered by springs or weights (balance).
Double Hung Replacement System
A packaged system furnishing new sash and operating block and tackle mechanism powered by springs or weights (balance). For replacement of sash only in double hung windows found in older buildings.
Dry Glazing
An alternative method of placing glass in a door or window. No glazing mastic is used.
Drip Cap
A piece of flashing which is contoured for application on top of windows and doors during installation. Its purpose is to prevent water from seeping down behind the casing and invading the interior of the wall. For Clad windows this item is often incorporated into the head nailing flange.
Edge Glued
A method of developing wood composites to provide wood parts with greater width. The width is achieved by gluing the smaller component wood pieces edge to edge.
Egress
Literally, an exit (a means of exit). Actual open size determined by local building code.
Energy Panel
This device is a single piece of glass whose edges are protected by an aluminum surround. Its purpose is to increase thermal efficiency on single glazed, 15/16" bar true divided lite units.
Extension Jamb
Wood parts which are nailed to the inside edges of the window jamb to extend it in width and adapt it to a thicker wall.
Frame
The outer components of a window unit-side jambs, head jamb and sill (bottom jamb). These parts Frame" the sash in an operating window and form an immediate boundary for the glass in a direct fixed unit.
Frame Dimension
Measurement from outside of side jamb to outside of side jamb or from outside of head jamb to outside of sill (bottom jamb).
Finger Joint
A method of joining wood parts end to end by machining a series of finger-like grooves in their ends. As they are interlocked, the fingers are bonded together with adhesive.
Flanker
The designation given to units that flank a center picture unit in a double or triple combination or bay window.
Flat Casing
An exterior trim alternative to brick mould. This stock does not have a profile but is simply surfaced flat on four sides.
French Patio Door
A type of swinging patio door which features two operating panels. One panel is designated as the active panel and is equipped with the active handle and latch set. The secondary inactive panel is equipped with flush bolts at head and sill allowing it to be fixed in place or to swing freely. The unit which has just been described is a Traditional or authentic French door.
Center Swinging Patio Door
A center swinging patio door attempts to project the feeling of an authentic French door but it differs in two major ways:
A. Panel(s) is permanently fixed.
B. The operating panel is not hinged on the side jamb-instead the panel is hinged from a special structural mull in the center of the unit.
Geometric Windows
These are specialty windows classified as either of two types:
A. Straight Line Geometrics, rectangles, triangles, trapezoid, octagons, pentoids, etc.
B. Radius Geometrics-half rounds, quarter rounds, full rounds, sectors,ellipses, etc.
Glass Size
Actual Glass size, not merely that which is visible.
Glazing
May mean either the act of inserting glass into windows and doors are reference to the glass in a window or door.
Glazing selections include:
A. Single Glazing (S.G.). Just as the name implies, the unit is glazed with only one pane of glass.
B. Insulating Glazing (1. G.). Two panes of glass permanently bonded together with a spacer to separate them and create a captive air space.
C. Triple pane-a sealed insulated unit composed of three separate panes of glass with two spacers producing two distinct captive air spaces.
Grilles
Simulated maintains and bars which don't actually divide the lites of glass. Classed as "full surround" all horizontal and vertical tears are linked at the perimeter by a wood surround, or Stick-bars not linked at perimeter (also called grids).
Hopper
Type of window hinged on the sides or bottom that opens at the top by swinging in or out.
Insulated unit
Two pieces og glazing (glass) separated by a spacer for improved thermal efficiency.
Jamb Liner
A weatherstrip device which, in double hung windows, lines the two vertical sides of the sash opening. In addition to providing a tight fit between sashes and the frame it also serves as a mounting site for the block and tackle and coiled spring operating mechanism.
Laminating
A method of bonding an overlay(wood acrylic etc.) to a window component.
Lineal Footage
A dimension expressing length (in feet) only. For example, the width of a unit (in inches) plus the height (in inches) x 2 divided by 12 = the perimeter measurement of the unit in lineal feet.
Low E
A name given to a special energy flow control glass. When speaking of heat radiation, objects which readily give off the heat they possess are said to have high emissivity. By applying a microscopically thin, transparent, metallic coating to the object's (glass) surface its emissivity is dramatically reduced. Thus it now has low emissivity-Low E glass.
Masonry, Clips
Special metal strip accessories designed to secure window or door units in masonry openings.
Masonry, Opening
An opening created in brick, stone or block to accept a window or door unit.
Mullion
The joints which result when window or door units are combined by linking their frames to form multiple units. Mullions may be horizontal or vertical.
Also "mull" In addition to standard mulls, two special forms exist:
A. Space Mull-A greater space is left between the linked frames to "stretch" the multiple unit to fill an unusual rough opening. If a jamb extension is included it surrounds the entire unit.
B. Stud Pocket Mull-In this method of joining unit frames a greater space than usual is also left. However this is done to allow room for a support member (stud) to be placed between the units. In this instance jamb extensions, if required, surround each individual unit separately.
Muntins
The correct name for the dividing "bars" in True Divided Lite Glazing.
Nailing Fin (Flange)
A strip of sheet material (vinyl, Aluminum, steel etc.) which is integral to or fastened to the frame of units. This creates a flange which is a common method for installation of new construction windows and doors.
Picture Window
A large stationary (fixed) window which is designed for providing a maximum view without obstruction.
Primer
factory applied coating which is designed to promote better acceptance of a paint finish overcoat on the exterior surfaces of wood windows. All exterior wood parts should be primed. Primer is not a sealant and all primed products must have finish coats applied.
Projected Window
Casements and Awnings - project out when open
Rails
The horizontal (top and bottom) members of a window sash or door panel.
Rough Opening
The framed opening in a structure to accept a window or door unit. It allows for additional room around the frame for correct alignment.
Sash
A wood perimeter around the glass which allows some independent movement from the frame (not direct set).
Sash has two types of components:
Stiles-the vertical perimeter pieces
Rails-the horizontal perimeter pieces
Sash Opening
The space described by the interior of a window frame. It is bounded by the interior surface of the frames. Jamb liners or hardware adapters must be disregarded. (Primary use of this dimension is for the Replacement Double Hung System).
Sill
The horizontal member which forms the bottom of a window or door frame.
Sill Horn
An extension of a window's sill or sub sill beyond the outer surface of the frame side jambs. This extension provides a bottom contact point for the exterior trim.
Single Hung
Window system where only one glass unit is movable in plane of window.
Square Foot
A unit of measure for designating area One foot by one foot. Derived from width (in inches) x height (in inches) divided by 144 = area in square feet.
Stool
An interior sill extension used almost exclusively with double hung windows.
Stop
Types:
Glazing Stop (Glazing Bead)-a small wood strip used to hold glass in place.
Screen Stop - trim item attached to the frame of window units. Its provides a stop for placement of screens if the sash is to operate.
Subsill
A trim piece for windows. Subsill application (underneath the bottom jamb) simulates the appearance of a true sloped sill and also provides a drainage surface.
Transom
Generally refers to a fixed or operating window unit specifically designated for placement directly above a door or a window.
Stucco Brick Mould
Standard exterior trim which has been modified by having a groove cut in the top rear edge permitting exterior stucco to flow behind the trim.
Unit Dimensions
The dimensions of a window or door unit which are defined in a primed wood unit from outside of exterior trim to outside of exterior trim in both width and height. Unit dimensions for clad units are from outside of frame to outside of frame in width and height.
Vent
Part of window holding glass that opens.