We have compiled many of the terms you need to know regarding windows and created this easy to use glossary. If you haven't found what you are looking for, please contact us.

A

AAMA - The American Architectural Manufacturers Association, a national trade association that establishes voluntary standards for the window, door and skylight industry.http://www.aamanet.org/

Air Infiltration - The amount of air that passes between a window sash and frame. In windows it is measured in terms of cubic feet of air per minute, per square foot of area. The lower the number, the less air the window lets pass through.

Architectural Shape - Broken into two categories, curved shapes and angled shapes, every unit is built to a custom configuration. Standard custom picture windows are stationary, but some can be ordered as operable units. Example: octagons, and right and left trapezoids (with and without extended leg).

Arch-top - One of several terms used for a variety of window units with one or more curved frame members, often used over another window or door opening. Also referred to as circle-heads, circle-tops or round-tops.

Argon Gas - An odorless, colorless, tasteless, non-toxic gas, which is six times denser than air. It is used to replace air between the glass panes to reduce temperature transfer.

Awning Windows - Window with sash swinging outward from the bottom. (style guide)

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B

Balance System - Device for holding vertically sliding sash in any desired position through the use of a spring or weight to counterbalance the weight of the sash.

Basement Hopper – (see hopper window) (style guide)

Bay Window - A combination of window units which projects to the exterior. Usually features a large center unit with two flanking units at 30 or 45 degree angles to the wall. (style guide)

Bottom Rail - The bottom horizontal member of a window sash or door panel.

Bow Window - Giving the illusion of bowing a wall, the bow windows create subtle curve enhancing the interior space. The configuration consists of three or more adjoining window units. (style guide)

Brickmold - A form of exterior casing for windows and doors that serves as an aesthetic boundary between the siding and the frame.

Bulb Seal - A soft, rounded PVC weather-strip used where a compression type seal is required, providing a light and sound barrier with and aesthetic interrupt.

Butyl - A rubber material that seals the glass to the spacer, creating an airtight and watertight IG unit. Butyl has the lowest gas permeability of all rubbers.

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C

Cam Lock - A lever operated lock which is used to prevent intrusion through the sash. The lock will match the color of the vinyl.

Casement Window - Window with sash cranking outward, to the right or left. (style guide)

Casing - Exposed molding or profile around a window or door, on either the inside or outside, to cover the space between the window frame or door jamb and the wall.

Caulking - A compound for filling joints and sealing cracks to prevent leakage of water and air.

Circle-Top - One of several terms used for a variety of window units with one or more curved frame members, often used over another window or door opening. Also referred to as arch-tops, circle-heads, round-tops.

Clear Opening - Unobstructed area for exiting a window.

Colonial Contour Grids - these grids recreate the colonial-style of windows.

Condensation - Condensation comes from the moisture in the air, and is caused by too much moisture in the air for a certain temperature. Condensation forms when warm, moist air touches a surface that is colder than the dew point of the warm air. As that air becomes colder and its temperature drops below its dew point, it must release excess moisture to reach its new, lower dew point. It releases moisture in the form of water, which appears on the colder surface.

Convection - Heat transfer by currents that flow from a warm surface to a colder one.

Cottage Style - (pictured at left) Cottage style units have an unequal sash. The top sash is shorter than the bottom sash. Available in both single hung and double hung styles.

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D

Dead Lite - (see stationary panel)

Dead Panel - (see stationary panel)

Dew Point - is the temperature that the air will no longer hold its entire moisture vapor. (Cold air holds less moisture vapor than warm air).

Double glazing - Use of two panes of glass in a window to increase energy efficiency and provide other performance benefits. May or may not refer to an insulating glass unit.

Double-Hung Window - Featuring both upper and lower operable sashes, which both tilt inside for cleaning and operationally, sliding vertically past one another. (style guide)

Drip Cap - A molding or metal flashing placed on the exterior topside of a door or window frame to cause water to drip beyond the outside of the frame.

DP-50 Rating - this means that the product achieved a Design Pressure (DP) Rating of 50 or greater, which meets category B hurricane standards for maximum protection against storms in most coastal areas of the country. The higher DP rating, the better a window or patio door is able to handle storm conditions.

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E

Extension Jamb - A trim component which extends from the interior of the window frame to the interior wall.

Extrusion - A form produced by forcing material through a die.

F

Fenestration - Originally, an architectural term for arrangement of windows, doors, and other glazed areas in a wall. Has evolved to become a standard industry term for windows, doors, skylights, and other glazed building openings.

Fixed Lite - Non-venting or non-operating picture window.

Fixed Panel - Non-operable door usually combined with operable door unit.

Frame - The enclosure in which window sash(s) or door panels are mounted in.

Fusion-weld - A term used for a type of corner construction, used with vinyl and other types

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G

Garden Window - A garden window adds a light and dimension to any room. This window is a projecting three sided window, which can include shelving a glass top and two casement windows for air circulation. (style guide)

Geometric Window - (see Architectural Shape) (style guide)

Glazing - the process of sealing the insulated glass unit to the sash.

Glazing bead - A strip of vinyl, which surrounds the edge of the glass and holds it in place in conjunction with other sealants.

Grid - A decorative grid on the interior or exterior of the glass, between the glass panes, or in any combination of these locations that divides a window opening into smaller openings to create simulated divided lite or true divided lite. Grilles may or may not be removable.

Grille - (see grid)

H

Head - Main horizontal frame member at the top of a window or door.

Hopper Windows - Inverted versions of awnings that are used typically in basements. They're bottom-hinged to swing in from the top. (style guide)

Horizontal Slider - A window with a moveable sash that slides horizontally.

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I

IG - (insulated glass unit) An enclosed, dehydrated and hermetically sealed air space between the panes of glass. The sealed air space may contain air or be filled with an inert gas, such as argon.

In-Operable Sash - (see stationary panel)

Interior Grids - or between the glass grids are permanently sealed grids between the two panes of insulating glass, making it easier to clean the glass surface.

J

J-Channel - Integral extension on the outside perimeter of a new construction window that eases installation on siding applications.

Jamb – A vertical member at the side of the window frame. Also can refer to the horizontal member at the top of a window frame, as in Head Jamb and Window Jamb.

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K

Keeper - A bracket utilized as a latching point for the bolt, cam or latch.

(KD) Knock-Down - Unassembled window or door unit.

L

Laminate - a material adhered to the vinyl giving it the appearance of wood grain. (Available from Seven D Industries in both light and dark wood on white or tan vinyl.)

Lift Rail - A handhold for raising and lowering the sash. Rail implies that the handhold is continuous across the sash.

Lite - (also light) A pane of glass within a window. Double hung windows are designated by the number of lites in upper and lower sashes as in 6 over 6.

Lock Rail – (see meeting rail)

Low-Emissivity Glass (Low-E) - Glass with a transparent metallic oxide coating applied onto or into a glass surface. The coating allows short-wave energy to pass through but reflects long-wave infrared energy, which improves the U-value.

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M

MDF - Medium-density fiberboard. A wood-fiber composite used in a variety of window, door, and millwork applications.

Meeting Rail - The horizontal sections of a pair of sashes that meet when the sashes are closed.

Mechanical Window - A term for a product, usually vinyl, in which the corners are assembled using screws or other fastening mechanisms, as opposed to a welded construction. Also referred to as a mechanically-fastened window.

Mulled Unit - Two or more window units structurally joined together.

Mullion - A vertical or horizontal connecting unit between two or more windows.

Muntin - Profile or molding, either vertical or horizontal, used to separate glass in a sash into multiple lites. Generally refers to components used to construct divided lite grids or grilles simulating a divided lite look. (see grid)

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N

Nailing Fin - An accessory component or integral extension of a window or patio door frame which generally laps over the conventional stud construction and through which nails are driven to secure the frame in place.

(NFRC) National Fenestration Rating Council - is a non-profit, public/private organization created by the window, door and skylight industry. It is comprised of manufacturers, suppliers, builders, architects and designers, specifiers, code officials, utilities and government agencies. NFRC provides consistent ratings on window, door and skylight products. http://www.nfrc.org/

O

Obscure Glass - Glass that has been made translucent instead of transparent.

Operable Sash - An assembly, mounted on a sash rail, comprised of stiles (vertical pieces), rails (horizontal pieces), and a window’s glass that opens and closes.

Oriel Windows - (pictured at left) Oriel style units have an unequal sash. The top sash is longer than the bottom sash. Available in both single hung and double hung styles.

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P

Palladian - A Palladian is a large built up unit, which is divided into multiple parts and is generally comprised of a mixture of operable and fixed shapes. (style guide)

Patio Door - A mainly glass door that opens onto a patio, deck or backyard of a house. The door panel is comprised of operable and stationary units. (style guide)

Picture Window – A large stationary, complimentary windows that can be added to most any combination to enhance the beauty of the piece. (style guide)

Q

R

Rail - The horizontal members on the framework of a sash or panel.

Rough Opening - The framed opening in a wall where a window or door is to be installed.

Round-Top - One of several terms used for a variety of windows units with one or more curved frame members, often used over another window or door opening. Also referred to as arch-tops, circle-tops and circle-heads.

R-Value - Resistance a material has to heat flow. The higher the R-value, the greater the resistance.

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S

Sash - The operable/inoperable part(s) of the window which holds the glass in place.

Sash Interlock - provides a positive tight seal where top and bottom sash come together.

Sash Lift - Protruding or receded handle on the inside bottom rail of the lower sash on a hung window.

Sidelite - A fixed, usually rectangular window placed on either side of a window or patio door.

Sill - A main horizontal member forming the bottom of the frame of a window or door.

Single-Hung Window - Providing a classic appearance to any home, featuring one stationary sash at the top and one bottom operable sash that tilts into the home for ease in cleaning. (style guide)

Slider Window - The slider window gives a more streamlined look with a mixture of horizontal fixed or moveable sashes. (style guide)

Sloped Sill - A main horizontal member forming the bottom of the frame of a window or door. Allows for efficient water drainage and provides the unit with a traditional wood look.

Stationary Sash or Panel - A window sash or patio door panel, often used in combination with other types of window and sash units, that is fixed to the frame and intended primarily for viewing purposes and for admitting light.

Spacer - Material placed between two or more pieces of glass in order to maintain a uniform width between the glass panels, and prevent sealant distortion.

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T

Tempered Glass - Glass with a surface compression of not less than 10,000 psi, or an edge compression of not less than 9,700 psi. When broken, the glass breaks into pebbles instead of shards.

Tilt Latch - Mechanism that releases the sash and allows it to tilt in from the main frame.

Transom - A fixed window, usually rectangular, placed over a door or window. Transoms, or fanlites, were first used in the 18th century on exterior doors. (style guide)

U

U-Factor/U-Value - Amount of heat transferred through a material. The lower the U-value, the slower the rate of heat flow and the better the insulating quality.

V

Vent - the area of the opening allowing ventilation through an open window.

Visible Lite - A lite or cutout formed by a vertical and horizontal bar extending from rail to rail of a sash or door.

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W

Weather-stripping - Variously shaped metal, vinyl, plastic or molded fiber strips that fit tightly against the window or door frame parts to prevent air infiltration through cracks. Cold air entering the house in winter can account for up to 35% of the heating load. Weather-stripping can reduce the load to 20%.

Weep Hole - The visible exit or entry part of a water drainage system used to drain water out of a window or patio door.

Weld - A term used for a type of corner construction, used with vinyl types of windows and doors, in which a small amount of material at the two pieces are melted or softened, then pushed together to form a single piece. This is also referred to commonly as a fusion-weld.

XYZ

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