GLOSSARY
a b c d e f g h i j k l m n o p q r s t u v w x y z abbreviations
annealed: normal glass that is cooled so that it can be cut by scribing and snapping. It is not safety glazing.
apron: the lower member of interior window casing, which is installed under a projecting stool or sill. Also sometimes used under sill projection at the exterior of frame.
archtop: see curved top.
astragal: a molding that is attached to one of the two meeting stiles to provide weather protection. Astragals can be flat or T shaped.
awning: window where the sash opens out at the bottom (hinged at the top).
bar: a horizontal glazing member of a sash. Bars run continuously from one side of a sash to the other. See muntin.
bead: a decorative half-round shape along the meeting stile of a pair of casement sash. It is placed opposite the rabbeted edge to balance the appearance of the two stiles. Other millwork molding can also have beaded edges.
blind stop: a stop applied to the outside edge of the jambs which holds the sash in place, typical on a double hung window. It is partly covered by the exterior casing, hence the name blind stop.
bowed sash: where the sash appears curved in plan. Also known as bent sash. Our curved sash parts are typically sawn from solid wood. Glass can also be fabricated "bent" with the same curve.
bronze: 1) a metal alloy of copper and tin. 2) a color choice which is similar to dark brown. "BRONZE" color may vary between manufacturers.
callout size (CO): the window dimension often called out on plans or schedules. It can sometimes be the actual opening for the sash in the frame, but should always be clarified as to what it is intended to be.
casement: a window sash that opens on hinges at one side. It can either swing out or swing in.
casement pair: two casement sash installed in a single frame opening that meet (and usually lap) at the center. Also known as a French casement.
casing: trim that is applied around the edge of the window frame and finishes the space between the wall and the window frame. There can be exterior and interior casings. It can be mitered or square cut at the corners.
check rails: horizontal parts of double hung sash where the upper and lower sash meet. These rails usually have strips that check air infiltration. The profile can vary and they may or may not be weather-stripped. Most old double hung sash have stepped check rails.
check stiles: vertical parts of (horizontal) sliding sash very similar to check rails above.
clearance: required spaces between sash and frames for operating hardware to function properly, and allow for seasonal movement. It varies depending on the hardware type and application.
clerestory: a wall that rises above an adjoining roof and may contain windows.
cope: the shape on the end of a sash member that is cut to mate with the shape on the sticking. It is found on the ends of rails, bars and muntins; whereas the sticking is found on the edge of these parts (and the stiles).
curved top: a window where the top rail and head are built curved. The curve can be circular, elliptical, or other irregular pattern. The circular head is most economical to build.
dado: a rectangular groove cut across the grain in a piece of wood.
diamond light: part of a sash where the bars and muntin run regularly diagonal instead of horizontal and vertical.
dormer: a window set vertically in a wall projecting through a sloping roof. The dormer structure has a roof of its own.
double hung: window with two operable sash sliding vertically in parallel tracks. The upper sash is towards the outside while the lower sash is towards the inside.
elliptical top: oval shape window head, usually half-ellipse. We typically build true ellipses, not approximations, because they look better.
fan light: a sash with muntins radiating out from a central point at the bottom. They may or may not come together at a hub. Fan lights are often part of curved top sash, especially transoms.
finish opening (FO) the overall finish opening for the sash. It is also the inside measurement of a window frame where it fits tight to the sash.
finish size (FS) the actual size of sash after allowing for operating clearances.
fixed: window where the sash are not operable. This is not the same as direct glazed, which has no sash at all, only glass directly glazed into a wood frame. Some fixed windows may be made to look like other types such as double hung or casement pairs.
frame: the part of the window that fits into the rough opening and holds the sash. A window frame usually has a sloped sill.
French door: (or sash) any wood door with glass. It may be one-light or multi-light.
groove: a slot cut parallel with the grain in a piece of wood.
head: the top part of a window frame. It may actually be made up of many pieces, including stops.
hopper: window which opens in at the top, hinged at the bottom.
horns: the projecting ends of a sill or stool that provide a place for the bottom of the side casing to end. They are measured from the inside of the jamb to the end of the horn.
hub: a sash part where the muntin ends of a fan light converge. It is usually semicircular.
interior stop: a frame part applied to the head and side jambs, creating the sash rabbet or track. It can be made with a shaped edge or square cut.
jamb: the part that forms the side and top of a window frame. It is also called side jamb and head jamb.
laminated safety sheet (LSS) glass that has two pieces of glass bonded to a center layer of plastic. This prevents broken glass shards from falling. It also greatly reduces ultraviolet light and sound transmission.
low E glass (hardcoat): a high performance glass. One of the surfaces has an almost invisible coating that increases the insulating value.
low E2 glass (softcoat) : similar to low E glass, only higher performance. It increases the insulating value even more and also significantly reduces the UV light transmission.
lugs: an extension of the stile, below the bottom rail of a double hung upper sash. It is usually ogee shaped, and is both decorative and allows a more substantial tenon at the check rail.
meat: the width of a sash member that remains after the glass rabbet(s) has been shaped away. The meat and the rabbet(s) added together make up the net width.
meeting rails: 1) another term for check rails. 2) the horizontal parts where stack awnings overlap. They are usually rabbeted and beveled to keep out the weather. They may or may not be weather-stripped.
meeting stiles: the vertical parts at the center of a casement pair (or triple) that usually overlap, and are rabbeted to keep out the weather. They typically have a decorative bead on one side that helps balance the appearance of the two stiles. Multiple casement sash may instead have a mullion between them, especially if there are wood screens.
mill finish: silver aluminum color.
mortise: the rectangular hole cut into the edge of a piece of wood (usually a sash part) that receives a matching tenon cut on the end of another piece.
mullion: a vertical frame part between two sash. It can be made solid, or of two jambs with a space between them.
muntin: (mutt or munt) vertical glazing member of a sash. In a multi-light sash, the muntins are discontinuous where they intersect bars.
nine light marginal: an arrangement of lights within a sash that forms small squares at the four corners. Each square typically has 3-4 inches of daylight or glass showing.
ogee: a molding made of two reverse curves.
oil-rubbed bronze: a premium metal finish which is a very dark brown color with a satin sheen.
outside dimension: (OD) the outside frame dimension of a window frame. OD plus shim space equals the rough opening size.
ovalo: a molding made of a radius and step reveal.
parting bead: the wood piece fitted into a groove in a double hung window jamb that separates the upper and lower sash runs. It must be removable to access the upper sash.
plow: (plough) the groove cut into the stile of a double hung sash to receive a sash cord. The groove has a hole bored at its lower end to hold the knotted end of the sash cord.
putty: soft compound used to seal the exterior of a piece of glass. It also forms a slope away from the glass to encourage water to run off. Putty is not compatible with insulating glass.
rabbet: a groove cut along the edge of a sash or a piece of wood.
rail: the top and bottom horizontal parts of a sash (or door).
RollAway: screen cloth which is fitted into a metal box that rolls up and down like a window shade. There is a drawbar to operate the screen and tracks on each side.
rough opening (RO): the hole in a building wall that receives the window frame.
sash: the part of the window that holds the glass. Sash fit into the frame. Sash may be fixed or operable (such as casement or double hung).
sash balance: one type of operating hardware for double hung windows. It contains a spring mechanism that provides a counterbalancing force, which keeps a sash up in its frame. There are different types of spring balances: duplex, spiral, block and tackle. They serve the same purpose as the sash cords, pulley and counterweights of the old double hung windows.
shim space: space left between the rough opening and outside of the window frame to allow for framing inaccuracies and to install the window frame plumb and level. It may vary depending on the plans.
sill: the bottom horizontal member of a window frame, usually made of redwood, and sloped to encourage rain water to runoff outside the building.
sill projection: part of the sill that projects beyond the outside edge of the window frame. It encourages water to run off well beyond the exterior wall surface keeping it out of the wall. Sill horns are usually an extension of this projection at each side of the frame.
single hung window (SH):window with two sash, top and bottom. It is similar to a double hung, but only the bottom sash is operable.
slider: (SL) window with two sash side-by-side where one sash slides horizontally. Although the other sash is usually fixed, it can also be built to slide. There can also be more than two sash.
spring bolt: metal hardware that has spring loaded pins, which mount into the stiles of screens to fix them in place.
stain grade: a better grade of finish than paint grade. The wood is carefully selected for minimal visible defects and matching color. SWC does not recommend stain finishes on the outside surface.
step: a detail that may occur as part of a sash or frame which generally increases weather protection by inhibiting air or water infiltration. Examples include stepped check rails or stepped sills.
sticking: molding cut into the edge of sash parts that forms the glass rabbet. It is typically an integral part of the sash, rather than applied.
stile: vertical perimeter parts of a sash. There is a left and a right stile for every rectangular or square sash.
stool: horizontal part of the window frame that is located on the inside, on top of the sill. Stools may be flush to the inside edge, or projecting into the room.
stool projection: an optional part of the stool that projects into the room, allowing the window frame to be cased differently, and also making the stool wider than a flush stool.
stop: a piece of wood that holds another part in place. Glazing stops are installed against the outside of the glass to keep it in the sash. Frame stops are installed against the jambs to create a rabbet for the sash to rest against. Stops can either be applied or solid (cut out as part of a jamb). It depends upon the application.
tempered: glass that has been heat-treated to make it stronger and resistant to breaking. When tempered glass breaks it shatters into smaller and safer pieces. Tempered glass usually has a small logo in a corner verifying that it is safety glazing.
tenon: the half of the mortise and tenon joint which is inserted into the mortise. This joint is recognized to be superior to others because of the large glue surface it creates.
transom: a window located above another window (or door). It can be fixed or operable. If operable, it is usually as an awning or hopper-type sash.
transom sill: a horizontal frame member that divides the window, often between a transom, and the door or sash below.
trim: parts attached around the inside and outside of a window frame. It may include casing, stool, apron, or other stops.
visible glass size(VGS): the amount of clear glass between the sash members as measured from the inside edge of the sticking.
window: a glazed opening in the wall of a building. It may include a frame with or without sash.
ABBREVIATIONS
B/O by others
BS: blind stop
BSI: Balance Systems Inc. (block & tackle dh balances)
CKRL: check rail (double hung)
CLR: clear
CO: callout size
CAH: clear, all heart (redwood
DH: double hung
DSB: double strength glass, B grade
DWG: drawing, as in shop drawing
FAS: firsts and seconds (grade of hardwood)
FO: finish opening, sash opening size
FS: finish size
GO: glass opening size
IG: insulated glass or dual glazing
KD: kiln dried (lumber)
LH: left hand
LSS: laminated safety sheet
MG: mixed grain (lumber)
MIN: minimum
NF: non-friction, as in casement hinges
OA: overall (size)
OD: outside (frame) dimension
OG: ogee (sticking)
ORB: oil-rubbed bronze
OS: old style (sticking)
PF: polyflex (weatherstrip)
PB: parting bead
PROJ: projection, as in projecting sills or stools
PT GR: paint grade
QLON: perimeter leaf weatherstrip
CT:Conservation Technology (weatherstrip company)
RH: right hand
RO: rough opening
RWD: redwood
S4S: surfaced four sides (lumber)
SGL GLZ: single glazed
SIM: similar
SSB: single strength glass, B grade
STD: standard
ST GR: stain grade
SW IN: swing in
SW OUT: swing out
(T): tempered glass
UON: unless otherwise noted
VG: vertical grain
VGS: visible glass size (daylight)
WS: weatherstrip
XOS: expanded old style (sticking)
BAB: bronze air bar (dark)
CAB: champagne air bar
SAB: satin air bar (silver)
WAB: white air bar
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