Glossary

A/C Panel – Also referred to as an Insulated Aluminum Panel. This panel is installed in a sash in place of an IGU. This panel is often constructed of two aluminum plates with an insulating material in between. This window option is often used to provide an area to connect any appliances that need to vent to

Argon Gas – A fairly inexpensive gas used in IGUs to provide a more energy efficient window. The nature of Argon Gas is much denser than air, thus providing a better insulating effect.

Awning Window – Top-hinged single sash window that vents outwards. (picture)

Balance – A device installed on opposing sides of a single-hung or double-hung window frame to counterbalance the sliding sashes. The design of the balance allows for the sash to be held open at any given position.

Bay Window – A window system that projects out from the wall. Not to be confused with a Bow Window, Bay Windows consist of three lites, wherein the center lite is usually about ½ the total width and is fixed. The two side lites are usually operable and can be either Casement or Double Hung Windows. (pic)

Beveled – Beveled is a term used to describe something that has a sloping angle in order to give it an appealing look. In the case of windows, the frame is often times beveled to give the window a better curb appeal.

Block & Tackle Balance – Block & Tackle Balances are a type of balance that operates on a nylon pulley and counterweight system.

Bow Window – A window system that projects out from the wall. Not to be confused with a Bay Window, Bow Windows consist of multiple equal lites which gives it an arch-like shape. Each lite usually consists of any combination of fixed lites and Casement Windows. (pic)

Brick Molding – The Brick Molding is a trim piece used to cover the gap between the window frame and masonry or whatever siding material is used.

Cameo Window – Cameo Windows are fixed oval windows, generally with surrounding moldings and ornaments. These windows are commonly found in Colonial Revival houses.

Cam Lock & Keep – The Cam Lock & Keep are the two pieces of hardware that locks the sashes of an operable window in a closed position. These locks are usual manually operated.

Casement Window – Side-hinged single sash window that vents outwards from either the left or right. (picture)

Casing – Casing is an exposed molding or framing around a window or door, on either the inside or outside, to cover the space between the window frame or jamb and the wall.

Coil Balance – Also referred to as a Constant Force Balance. Coil Balances are a type of balance that operates using a heavy duty steel coil spring.

Colonial Grids – Colonial Grids are a style of grids that have a flat shape to them and are usually arranged in square/rectangular patterns.

Constant Force Balance – Also referred to as a Coil Balance. Constant Force Balances are a type of balance that operates using a heavy duty steel coil spring.

Cottage Style Window – Sometimes referred to as an Oriel Style Window. This style refers to a Vertical Slider that has the top sash shorter than the bottom sash.

Daylight – Not to be confused with Deadlite. Daylight is the term used to express the visible transparent area of the window.

Deadlite – Not to be confused with Daylight. Nor should it be confused with a Picture Window. A Deadlite is a type of window that has the most basic of frames. It is usually no more than a fixed sash.

Desiccant – A material commonly used in the seal of the IGU. It absorbs moisture in the air and helps prevent against condensation and frost from forming inside the window.

Diamond Grids – Also known as Lattice or Lozenge Grids. Diamond Grids describe a pattern of grids that are arranged in diagonals to perform a lattice pattern.

Double Glazing – Double Glazing refers to an IGU with the two inner surfaces of the glass panes glazed to help provide the best insulation possible.

Double Hung Window – Sometimes referred to as a Vertical Slider or Double Hung Tilt. A Double Hung Window consists of two operable sashes that slide up and down to provide ventilation. They are usually capable of being tilted inwards for maintenance. This is the most common window for most homes.

Expander – This is an extruded accessory piece to the window frame. It is generally the same depth as the frame and attached on top of the window to help close any gaps that may occur between the window frame and jamb.

Extension Jamb – An Extension Jamb is a board attached to the frame of the window to increase the depth in order to fit a wall of any given thickness.

Fixed – A term used to describe windows that are not operable.

Flashing – Flashing is the material installed around windows designed to prevent water from entering between gaps in adjoining building surfaces.

Float Glass – Also referred to as Hard Coat Low E Glass. This type of glass refers to a specially coated glass that gives the IGU better energy saving performance. This is the older technology of Low E glass available in today’s market. The other newer and better performing technology of Low E glass available is Soft Coat Low E Glass.

Garden Window – A window system that projects out from the wall and is encased by glass on all sides, except for the seat. This window system generally consists of four lites. Three of which form the three sides of the window at 90 degree angles and the fourth which forms the sloped top of the window. The front and top windows are fixed, while the side lites are usually operable. (pic)

Georgian Grids – Georgian Grids are a style of grids that have a contoured shape to them and are usually arranged in square/rectangular patterns.

Glazing – Glazing is the installation of glass in a window opening.

Glazing Bead – Also known as a Glazing or Glass Stop. This is a removable trim that holds the glass panel in place inside the window sash.

Hard Coat Low E Glass – Also referred to as Float Glass. This type of glass refers to a specially coated glass that gives the IGU better energy saving performance. This is the older technology of Low E glass available in today’s market. The other newer and better performing technology of Low E glass available is Soft Coat Low E Glass.

Hopper Window – Bottom-hinged single sash window that vents inwards. (picture)

Horizontal Slider – Also simply referred to as a Slider. A Slider consists of operable sashes that slide side to side to provide ventilation.

Insulating Glass Unit (IGU) – Often referred to as an IGU, an Insulated Glass Unit refers to the glass package that consists of multiple panes of glass (usually two or three). One or more surfaces of the glass panes may be glazed to provide improved insulating qualities.

Insulated Aluminum Panel – Also referred to as an A/C Panel. This panel is installed in a sash in place of an IGU. This panel is often constructed of two aluminum plates with an insulating material in between. This window option is often used to provide an area to connect any appliances that need to vent to

Jamb – The jamb refers to the wood member at the side of the window frame. The jamb can also be referred to the horizontal member at the top of the window frame, in which case, it is also referred to as a Head Jamb or Window Jamb.

J Channel – A J Channel is an extension from the exterior frame of a window. It helps with the integration of the window and siding by covering the edges of the siding material.

Krypton Gas – A gas used in IGUs to provide a more energy efficient window. The nature of Krypton Gas is denser than air and Argon Gas, thus providing a better insulating effect. It does cost significantly more than Argon Gas and performs only marginally better, which is why most manufacturers stick to just Argon Gas.

Lift Rail – This is the protruding bottom horizontal member of the bottom window sash in a Double Hung Window. It is used to lift the operable sash up to vent.

Lite – A Lite is a term used to describe each section of daylight.

Lock Rail – Also known as a Meeting Rail. The Lock Rail is the bar that meets on either of the sashes on a Horizontal or Vertical Slider. The seal at this point is important for the purpose of insulation.

Marine Glazing – The Marine Glazing is a silicone piece wrapped around the entire IGU in an aluminum window. This is used to help keep the IGU in place and to provide a seal to protect against weather effects.

Meeting Rail – Also known as a Lock Rail. The Meeting Rail is the bar that meets on either of the sashes on a Horizontal or Vertical Slider. The seal at this point is important for the purpose of insulation.

Mullion – A component used between window units to join them. This is usually used for window systems going into large window openings.

Muntin – A Muntin is the name used for the actual extrusions used to form a grid pattern on a window.

Nailing Fin – A Nailing Fin is a piece found on new construction windows to allow for easier installation. It is a flat extending piece that runs around the circumference of the window at middle depth. It has several holes along it so that the window can be nailed into place.

National Fenestration Rating Council (NFRC) – The NFRC is the leading authorization organization responsible for certifying window test results. They certify ratings of a window’s U-Factor, Solar Heat Gain Coefficient, and Visible Transmittance.

Obscured Glass – Also referred to as Privacy Glass. Obscured Glass can come in a variety of styles and patterns. In general, it is a term used to describe glass that will allow light to pass through without being able to see clearly through it.

Operable Window – An Operable Window is simply any window that can be opened for ventilation.

Oriel Style Window – This style of window refers to a Double Hung Window that has the bottom sash shorter than the top sash. This term is also used sometimes when the top sash is shorter than the bottom sash, also known as a Cottage Style Window.

Picture Window – A Picture Window is a fixed window consisting of an inoperable sash within a frame. Not to be confused with a Deadlite.

Prairie Grids – Prairie Grids are a style of grids that are arranged in a rectangular pattern that consists of four muntin bars that are arranged to form four rectangles along the sides of the sash and four equal squares in the corners.

Privacy Glass – Also referred to as Obscured Glass. Privacy Glass can come in a variety of styles and patterns. In general, it is a term used to describe glass that will allow light to pass through without being able to see clearly through it.

Projected Window – A Projected Window is basically any window that projects inward or outward.

Pull Rail – This is the protruding top horizontal member of the top window sash in a Double Hung Window. It is used to pull the operable sash down to vent.

Sash – The Sash of a window is a component that consists of the IGU and the casing around it.

Sill – The Sill of the window is the bottom pan of the window. This design of this part of the window is important to draining water from the window.

Sill Angle – A Sill Angle is an attachment piece to the sill of the actual window. It extends down from the front edge of the window to cover any gaps between the window and a sloped opening.

Single Hung Window – Also referred to as a Single Hung Tilt. A Single Hung Window consists of one operable sash that slide up and down to provide ventilation. It is usually capable of being tilted inwards for maintenance.

Skylight Window – Skylights are quite different than most windows. They usually consist of a single lite, which gets installed on a rooftop. Skylights can either be fixed or venting.

Slider – Also referred to as a Horizontal Slider. A Slider consists of operable sashes that slide side to side to provide ventilation.

Soft Coat Low E Glass – Also referred to as Sputter Coat. This type of glass refers to a specially coated glass that gives the IGU better energy saving performance. This is the newer and better performing technology of Low E glass available in today’s market. The other older technology of Low E glass available is Hard Coat Low E Glass.

Solar Heat Gain Coefficient (SHGC) – SHGC measures how well a window blocks heat from the sun. It is expressed as a number between 0 and 1. The lower the SHGC, the better a product is at blocking unwanted heat.

Spacer – A Spacer is a component of an IGU that holds the two panes of glass in place. The Spacer is also an important piece in the insulation of a window. It is the Spacer and Seal that helps maintain the integrity of the insulating layer of air or gas within the IGU.

Spandrel Glass – Spandrel Glass is a type of glass that has practically no visible transmittance. This type of glass can come in a variety of colors and is usually used for architectural applications.

Spiral Balance – Spiral Balances are a type of balance that operates using spiral rods.

Sputter Coat Low E Glass – Also referred to as Soft Coat. This type of glass refers to a specially coated glass that gives the IGU better energy saving performance. This is the newer and better performing technology of Low E glass available in today’s market. The other older technology of Low E glass available is Hard Coat Low E Glass.

Steel Replica Window – Steel Replica Windows are specially made aluminum window systems designed to mimic the appearance of historical steel windows.

Tempered Glass – Tempered Glass is a safety glass that generally much stronger than the average glass used. Not only is it tougher to break, but it also does not break into shards when it does.

Thermal Break – A Thermal Break is polyurethane inserted between two sides of aluminum in an aluminum window. Due to the conducting nature of aluminum, a break is necessary in an aluminum window to provide much improved insulation.

Tilt Latch – A Tilt Latch is the latch mechanism on either side of an operable sash that can be released to allow for the sash to tilt inwards.

Transom – A Transom refers to the usually fixed window above a door.

Triple Glazing – Triple Glazing refers to an IGU with three panes of glass, each with one surface glazed to help provide a superior glass package over double paned IGUs.

U-Factor – U-Factor measures how well a window prevents heat from escaping a building. U-Factor ratings generally fall between 0.20 and 1.20. The lower the U-Factor, the better a product is at keeping heat in. Of note, U-Factor ratings between the U.S. and elsewhere in the world do not translate equally, since it is measured in metric units elsewhere.

Ultralift Balance – Ultralift Balances are a type of balance that operates using spiral rods in addition with specifically set tension springs. This type of balance is necessary for larger windows that have heavy sashes.

Ventilation Limit Latch – The Ventilation Limit Latch is a set of tabs installed into the sash of an operable window that, when open, prevents the window from opening beyond a certain point.

Vertical Slider – Also referred to as a Double Hung Tilt or Double Hung Window. A Vertical Slider consists of two operable sashes that slide up and down to provide ventilation. They are usually capable of being tilted inwards for maintenance. This is the most common window for most homes.

Virgin Vinyl – Virgin Vinyl refers to vinyl that is being used for the first time as opposed to recycled vinyl. Virgin Vinyl is generally stronger and is resistant against any discoloration.

Visible Transmittance (VT) – VT measures how much light comes through a window. It is expressed as a number between 0 and 1. The higher the VT, the higher the potential for daylight.

Weather-Stripping – Weather-Stripping is an insulation strip that is applied to the opening edges of an operable window or door to help prevent the occurrence of drafts and to provide better overall insulation.

Weep Hole – The Weep Hole is also known as a Weep Cut or Drip Cut. Weep Holes are holes or slits cut into the sill of a window to allow for water to drain out from certain areas of the window frame.