Window and Door Glossary

Window and Door Glossary

This window and door glossary is here to give definition to any and all of the terms you might encounter and not know.

2-Section Slider – a slider with 2 sashes.
242 or ¼-½- ¼  – a window configuration for triple units, meaning the middle unit is half the total width and the flankers are ¼ each.
3-Section Slider – a slider with 3 sashes, available in 242 or 333 configurations.  The middle windows is a picture window, with the flankers being operable.

333 or 1/3-1/3-1/3 – a window configuration for triple units, meaning all units are equal in size.
3/16” – Individual glass panes that are 3/16” thick (4.7mm)
6000 Series – The Tilt & Turn series, including:
Tilt & Turn Window
Tilt & Turn Twin Window
Inswing Door
Outswing Door
Twin Inswing Door
Twin Inswing Astragal
Twin Outswing Door Astragal
6000 Picture Door
6000 Picture Window
6000 No Sash Picture
7000 Series – Our basic line & profile:
2-Section Slider
3-Section Slider
Picture Window
The series is not available with insulating foam.
8000 Series – Our designer line & profile:
2-Section Slider
3-Section Slider
Double Hung
Picture Window
Casement Picture
Escape Window
Shape Windows
9000 Series – Our patio doors:
2, 3 & 4 Section Patio Doors


Accessories – Vinyl accessories that go with the windows.  This includes:
Brick Mould
Decorative Mullions
Flat Frame Adapter
Interior Frame Extendions
Mullion covers
Nailing Fin
Head & Sill Expanders
Sill Angle
Snap Mull
Annealed Glass – glass that has not been heat-treated or tempered.
Argon – an inert gas that is between the panes in an IGU, that acts as an insulator and stops heat transfer.
Astragal – a form of joining two components without having a fixed mullion in place (e.g. French Doors)
Awning (also Casement Awning) – only available in the 8000 series, it is a window that opens on a hinge vertically from the top, with a crank handle mechanism.  It has the casement profile.


Balance – the metal coil/spring that keeps the sashes on a double-hung in place.  At the bottom of the balance is the shoe, which is where the pivot bars of the sashes slot in.
Bay Window – a box that projects out from the house, typically with 3 openings available with angled projections (e.g. 15, 30, 45 degrees), with many options including pre-miter stops, insulated seat, turn-buckles, vinyl cladding and roofs.  It can have Double-Hungs, Picture Windows or Casements.  The Bay typically projects further out of the house than a Bow.
Blinds Between Glass –Our blinds are inside the IGU and are available in the 6000 & 9000 series.  We are the only manufacturer offering blinds with soft-coat LoE glass, as opposed to the less efficient hard-coat. Gas is not available in units with blinds.
Bow Window – a box that projects out of the house, typically with 4 or 5 openings, and in more of a semi-circular shape (less angular than a Bay).  It has many options including pre-miter stops, insulated seat, turn-buckles, vinyl cladding and roofs.  It can have Double-Hungs, Picture Windows or Casements.  The Bow typically projects out of the house less than a Bay.
Box – This is the wooden frame that makes up  a Bay or Bow.  We manufacture the windows that go in the box.  Available in Oak (recommended for staining) and Birch for (painting).


Cardinal Glass – our glass manufacturer and supplier, the global leader in the glass industry.  Manufactuers LoE, laminated, tempered and specialty glass panes and IGU’s.  Based in Madison, WI.
Casement – only available in the 8000 series, it is a window that opens on a hinge horizontally.  It is available with washable hardware or egress hinges.
Casement Awning – see Awning
Casement Picture Window – a picture window in the casement profile
Clear Glass – this is regular glass that has been untreated.
C-Mull – This a mullion that can be used to join windows with the Casement profile.
Codes – Each village, city or municipality has building codes it has to adhere to. This can effect u-factor, egress requirements and many other factors.  It is the responsibility of the contractor/dealer to ensure that they know the codes they need to hit, not ours.
Colonial – a grid pattern.
Condensation – is moisture that appears on cold surfaces in relation to humidity, temperature and dew point. There is a full fact sheet on condensation.
Confirmation – communication from client, in writing, that the quote has been checked for all measurements and specifications and that it is good to go into production. No job can be processed without a confirmation.
Contour Grids – This is the profile of the grid, or grid type. Contour is our standard profile and is a raised ridge running through the grid.  It is available to use or all grid configurations other than V-Groove.
Convection – This is the movement of air based upon heat and is a common reason for drafts.  There is a full fact sheet on convection.
Crank – This is the mechanism used on Awning & Casement windows.  It has an arm that is cranked, which makes the window open.  Also known as an operator.


Deceuninck – our vinyl supplier for 7000 & 8000 Series. Based in Monroe, OH. One of the world leaders in Vinyl.
Design Pressure – an architectural rating that measures the strength of the windows against wind. Used in commercial and high-rise applications.
Dew Point – the temperature at which dew (condensation) forms and is a measure of atmospheric moisture.
Dimensions – measurements – e.g. Width, Height, Thickness.
Double-Hung (DH) – available in 7000 & 8000 series, a window with two sashes that move vertically.
Double-Prairie – a grid pattern that has two lines going around the sash.
Double Strength – abbreviated to DS, it is thickness of the individual glass panes being used.  DS glass is 3.0mm thick.
Double Sunburst – a grid pattern available on circular shapes only].
DP – see Design Pressure
Dual Pane – Two glass panes joined together to make one unit.


Egress / Egress Requirements – Egress is the total net opening for a window – this means when it is open the total space from  surface to surface, for example with a Double Hung it isn’t the total size of the window but the total opening when it is at it’s maximum (the space between the sill and the bottom of the lock sash).  There is a national code for Egress Requirements, however this can vary based on municipality.  The national standard is 5.7 ft2.
Egress Hinge – a hinge on a casement that maximizes the net opening.  It brings the sash in line with the frame when opening, meaning it isn’t possible to clean it from the inside.
Energy Star – an independent organization set up by the Department of Energy to establish and measure a standard set of guidelines to recognize the energy efficiency of various products, including windows.  Meeting Energy Star standards can, in some cases, lead to tax credits.
Extrusion – how the vinyl is made – it is forced through (or extruded) through a mould to give it a certain profile.


Fixed Window –  see Picture Window
Flange – see Nailing Fin
Flankers – the windows on either end of a multiple unit.
Flat Grids – a grid type, in which the grids are flat (i.e. have no contours).
Foam –foam that is injected into the cavities in the vinyl profiles to provide extra insulation, hence also being referred to as insulating foam.  Only available in the 8000 series (not in the 6000 or 9000 series).
Folder – the job folder, that contains the confirmation and order print out, as well as any payment information.  When a job is allocated it goes to bookkeeping, after that it is kept in the main folder cabinet.  The folders are labeled with important information.
Frame – the framework that surrounds and supports the entire window, comprised of the head, sill and jamb.
Frosted – see Obscure
Fusion Welded – method to join PVC frame and/or sash members by heating the 45o miter cut ends, squeezing them together, allowing the assembly to cool, and trimming the weld excess.


Garden Window – a window that projects out from the house, almost like a greenhouse, with glass on all sides except the bottom.  They often have a shelf and are often used for plants
Glass Block – a square brick made from glass that can be stacked with other glass blocks.  They are typically 6” x 6”, or 8”x 8”.  As a result the total size can only be even.  There are options for a regular vent or a dryer vent.  Available in two styles, diamond or wavy.
Glass Specialty – the treatment on a glass, such as tempered, obscure, laminated, tinted.
Glass Surface Numbers – numbering system to identify glass surfaces, always starting form the extiror.  A typical IGU has four surfaces: #1 = the outside surface of the exterior lite; #2 = the inside surface of the exterior lite; #3 = the outside surface of the interior lite; #4 the inside surface of the interior lite.
Glazing Bead – A narrow strip of vinyl that with silicone sealant holds the glass in place within a sash or frame.
Grids – either metal or vinyl pieces of material that give the illusion that the glass in an IGU is being split in to numerous pieces.
Grid Type  – the type of material used for the grids, Contour, Flat, Pencil
Grid Patterns – types of pattern available with the grids, including Colonial, Prairie, V-Groove
Grilles – see Grids
Hard Coat LoE – transparent coating sprayed onto a glass surface while it is still hot, also known as pyrolitic LoE glass.  It is not as effective as soft-coat LoE glass.


Header – The main horizontal part of the window that forms the top part of the window frame.
Head Expander – U shaped extrusion slipped over the frame head that, when pushed up, closes the gap between the frame head and the opening head after window installation.
H-Mull – a vinyl accessory that is used to mull together windows with the DH profile (7000, 8000 DH, PW, SL)


i89 – a type of glass pane from Cardinal.  It is applied to the 4th surface, and in combination with other LoE glass types in a IGU provides superior performance in relation to U-Factor.  Using i89 is a surefire way to hit Energy Star ratings for 2016.
IGU – short for Insulated Glass Unit, also known as thermal unit.  A minimum of two pieces of glass, a spacer, hermetically sealed with butyl, to create one piece.  All of the windows we sell have IGU’s as a component.
Interlock – design feature on Double-Hungs and Sliders which allows sashes to engage with one another when closed.


J-Channel – a vinyl accessory which has a curved channel that the siding fits into, to make a weather tight seal.
Jamb – the main vertical parts forming the sides of a window frame
Jamb Depth – the depth (or thickness) of the wall that a unit is going into, essential for ordering Bay, Bow & Garden Windows.


Keeper – a piece of hardware that the lock slots into to make it secure. Found on windows, screens and doors.
Keeper Sash – the sash that has the keeper on it, with Double Hungs typically the top sash, with Sliders, typically the left sash.
Knee Braces –  a support system used for Bay/Bow & Garden Windows, in which two legs sit beneath the unit, physically supporting it.


Laminated Glass – two or more lites of glass bonded together under heat and pressure with a polyvinyl butyl inner layer.  Good for soundproofing.
Lite – single pane of glass, or number of panels (e.g. a 2-lite slider is the same as a 2-section slider)
Lock – the hardware that moves in a lock, catching with the keeper to securely fasten.
Lock Sash – the sash that has the lock on it, with Double Hungs typically the bottom sash, with Sliders typically the right sash.
LoE – shortened version of Low Emissivity, which means energy efficient, glass.
LoE-272 – our standard LoE glass, made by Cardinal, which has 2 layers of silver on the glass, creating superior energy performance and thus a lower u-factor
LoE-366 – our premium LoE glass, made by Cardinal, with 3 layers of silver on the glass, creating the best energy performance and a lower U-Factor.


Manifest – the paper that is printed out when someone picks up a job.  It allows the factory to find the items and it must be signed to show that the goods have been received.
Meeting Rail – part of a double hung where the two sashes meet and create a barrier.
Miters – the join between two pieces of material, at equal angles.
Mull – joining two or more units together with a mullion
Mullion – the piece of vinyl that is used to mull two or more units together. There are different types, such as C-Mull  or H-Mull.
Multiples – a category of windows that includes more than window joined together, for example a twin casement or a triple Double Hung.
Muntin – another word for grid


Nailing Fin – a vinyl accessory that skirts the frame of a unit and is used to attached it to it’s rough opening.
NEAT Glass – a 1st surface treatment to glass, manufactured by Cardinal, that has ‘low-maintenance’ properties. It is coated with a fine titanium-dioxide layer that when exposed to water acts as a catalyst to break down organic material, and thus leaving the glass clean.
NFRC – National Fenestration Rating Council, a non-profit organization which sponsors an energy efficiency certification and labeling program for windows and doors.  Each window/door we produce will have an NFRC sticker which will list U-Factor, SHGC, VT & Condensation Rating.
Night Locks – are a security feature and component on Double-Hungs and Sliders that are built into the sash.  They are small stops that come out that mean the window cannot be opened past a certain point from the outside.
No Sash – a style of picture window that doesn’t have a built in sash element, i.e. the glass goes right to the frame.


Obscure – a glass specialty in which one pane of the IGU is obscured or frosted.
Opening – vacant space/gap/hole
Operator – see Crank
Oriel – a double hung that has a meeting rail at any position other than in the middle, meaning the two sashes are different sizes.


Paint – all of paint is supplied by Blue River paints, it is scratch resistant and in darker colors it reflects heat back and thus avoids warping of frames.  We only paint the exteriors of the window.
Paintable Stainable – real wood finish applied to the inside of a window that can be painted or stained.
Pencil Grids – a grid type, thin and round like a pencil.
Perimeter Prairie – a grid pattern that goes around the perimeter of the glass.
PH Tech – a vinyl extruder that supplies us for the 6000 & 9000 series, based in Montreal, Canada.
Picture Window – a fixed window, i.e. no operable parts, available in the 7000 or 8000 series, using the Double-Hung Profile.
Pivot Bars – the bars on the bottom of a double hung sash that sit in the shoes as part of the balance system.  They are what enable the sash to stay in place.
Profile  – the shape of the vinyl extrusion.  We have four profiles, Double Hung, Casement, Tilt & Turn and Patio Doors.
Projection – the distance something  goes out from an exterior surface.


Rail – the horizontal piece of a window sash – comprised of the lower and upper rail
Rough Opening – the opening that the window/door frame will be going into.


Sample / Sample Box – a smaller window that is given to dealers to use as samples in their sales presentations. It comes packaged in a sample box so that it can be moved easily and remain protected.
Sash – the moveable part of a window.  The double hung and 2-section slider have 2 sashes each, whilst a casement, awning, hopper & escape window have just the one.  Picture Windows don’t have a sash at all, as they are fixed.
Scheduled (Order Status) – this is the stage after Allocated and means that the job is in production.  Once a job is scheduled it cannot be stopped or changed.
Screen – a woven mesh that is separate to the window and goes in front of the opening to allow air to pass through, but not insects.
Seal Failure – a common issue with IGU’s in which the seal around the glass unit fails, i.e. stops being airtight, and lets air,
Shape Window – a window that is not a standard rectangular shape.  There are linear shapes, which have straight edges, such as Octagons, Trapezoids.  There are also circular shapes, which have curved edges, such as arches, circle tops and eyebrows.
SHGC – see Solar Heat Gain Coefficient
Shoe – part of the balance system of a double hung in which the pivot bars sit.
Sidelite – available in the 9000 series, a sidelite is a fixed window that goes on the side of a Patio Door.
Sill – the main horizontal part forming the bottom of the frame of a window.
Single Prairie – a grid pattern
Slider – type of window available in 7000 & 8000 series. Available in 2 or 3 section windows.
Soft Coat LoE – transparent coating appli4ed to cool glass in a vacuum chamber, also known as sputter LoE. More efficient that Hard Coat LoE.
Solar Heat Gain Coefficient – also SGHC.  A criteria used on the NFRC labels on the windows.  The lower it is, the better – it means that less heat is being let into the home.
Spacer – the component that sits between glass, separating individual panes to make an IGU
Spokes – a grid pattern available only on shape windows, specifically circular shapes.
Starburst – a grid pattern available only on shape windows, specifically circular shapes
Stress Crack – a crack that appears in a glass unit, typically from the corners.  This can be a result of a number of things, but primarily it’s the glass adjusting to the temperature shift between seasons.
Sunburst – a grid pattern available only on shape windows, specifically circular shapes
Surface – see Glass Surface Numbers


Tempered – a treatment to glass that makes it much strong.  The glass is heated to a very high temperature and then rapidly brought down to room temperature.  It is four times stronger than annealed glass and will withstand severe impact force. If the glass does break it will crumble into many small pieces, rather than shards like regular glass.
Tilt & Turn – the 6000 series, windows in which the sash can both tilt inwards on a horizontal hinge (similar to a hopper, without the arms), or open outwards on a vertical hinge (like a casement but without the crank).
Tilt Release – a feature on the double-hungs which when activated allow the sash to tilt vertically to enable cleaning.
Tip to Tip – the measurement style we use for our ordering process – i.e. exact measurements from the tip of one edge to the tip of the other.
Transom – in the 9000 series, a transom is a fixed window that goes on top of a Patio Door.
Triple Glaze – instead of a traditional dual pane it is three lites joined together to make an IGU, with two spacers.
TTT – see Tip to Tip
Turn-Buckle – an option available with Bay /Bow & Garden Window, that acts as a support for the unit (as opposed to, or in conjunction with knee braces).


U-Factor – a criteria used by the NFRC in their labeling system, that measures heat transmission.  The lower it is, the better it is.  To meet Energy Star 2016 ratings, the U-Factor must be equal to or below 0.27.


Ventilation Latch – see Night Lock
V-Groove – a grid type in which the pattern is etched into the glass itself.
Vinyl – the material we use to manufacture our frames, sashes and vinyl accessories from.  We have two suppliers, Deceuninck and PH Tech.
Visible Transmittance (or VT) – one of the criteria the NFRC use in their labeling program, that measures how much light gets through an IGU. The higher the number, the better.


Washable Hardware – the default option for hinges on the Casement window, in which when opened there is a gap between the sash and the frame large enough to allow the exterior of the glass to be cleaned.
Weatherstripping  – strip of resilient material for covering the joint between the window sash and frame, in order to reduce air and water from entering.
Weep Hole – opening in a window sill and/or sash rail to allow water to drain to the exterior.
Welded – see fusion welded.
Woodgrain Laminates –an interior coating that looks like wood but is in fact a vinyl laminate, making it much more durable.  It is available in Light Oak, Dark Oak or Cherry.

We hope this window and door glossary has been useful – if you have any questions or would like to get in touch then contact us through our online Contact Form.


Window and Door Glossary