Search our window components terminology section and explore glossary terms related to window parts and features. Also of note, the following is 1 of 4 pages on our section dealing with definitions and terminology.
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Window Components Terminology | Parts And Features
Air Space
In double or triple glazed windows, this is the space that exists between the panes, which is filled with air for added insulation. Also, some windows replace the air in this space with gas for its increased insulative properties.
Argon Gas
A type of gas that is used to replace the air in double or triple glazed windows to increase the energy efficiency of the window by decreasing the amount of heat loss.
Balance System
A series of springs and/or weights placed within the sides of window frame that function to balance the weight of the sash so it remains in place when opened.
Center Sash
A sash that is hung or mounted on pivot pins in the center of the window so the sash can be pivoted open in order for easy cleaning.
Dessicant
A material that absorbs moisture and is in between insulated glass panes in multi-glazed windows.
Electrochromic Glazing
A special type of laminated glazing, or coating, that can be switched from tinted to clear and back again. Additionally, this increases energy efficiency, and can also increase privacy (when tinted).
Evacuated Glazing
Double and/or triple glazed windows use evacuated glazing between the panes.
Frame
The fixed part of the window (the perimeter) within which the sash or panes of glass are mounted.
Glazing Bead
A strip that holds the edges of a pane within the frame. Window manufacturers use wood or plastic for their glazing bead.
Head
The frame along the top of the window. Also called the ‘header.’
Head Expander
U-shaped filler (usually made of vinyl) on the head.
Heat Treated Glass
Window manufacturers strengthen glass by treating them with heat.
Hermetically Sealed Glass
Double or triple panes that are vacuum sealed in order to prevent the escape of air or gas within and to avoid the introduction of moisture.
Jamb
The frame members on each vertical side of a window (similar to the ‘head’ which is the frame member on the top of the window).
Additional Window Components Terminology
Krypton Gas
Krypton gas in between the panes of glass that improves the energy efficiency. Triple pane windows almost always contain krypton gas fills.
Laminated Glass
This includes a layer of plastic nestled between the multiple panes to improve impact resistance. Often used in hurricane or high wind prone areas.
Lite
Individual panes/frame sections within a larger window pane. For instance, an XOX contains three lite panels or insulated glass units.
Main Frame
Simply put, the main window frame.
Meeting Rail
Horizontal rails of two opposing window sashes that meet when the window is closed.
Obscure Glass
Obscure glass is glass that you cannot see through. Specifically, these come in different patterns and provide added decoration, light diffusion anbd/or privacy. Additionally, homeowners often use obscure glass in bathrooms.
Quarrel
A quarrel is a diamond shaped window glass. Specifically, one pane of glass uses multiple quarrels. Often, Gothic style home use quarrels.
Rail
The horizontal part of a sash on the top or bottom. Specifically, lift rails help homeowners open and close the window.
Rough Opening
The opening in the wall in which a window is mounted.
Sash
The sash is part of the window that contains the panes of glass. Essentially, sashes are the movable portion of the window.
Sill
The horizontal shelf that sits along the bottom interior of a window frame.
Tempered Glass
Tempered glass is very strong – much stronger than transitional low-e glass. Essentially, when a window pane breaks, it breaks into small square-ish pieces, rather than sharp shards. Further, companies use tempered glass for impact windows (for obvious reasons).
True Divided Light
TDT are small window panes that connect to one another through muntins.
Vent
A window vent is a small opening that provides ventilation.
Vinyl or Polyvinyl Chloride (PVC)
Manufacturers use PVC or polyvinyl chloride in the production process of vinyl windows. Specifically, PVC is does not conduct heat, is durable, and cheap to produce. Lastly, window manufacturers have improved the material to uPVC, which has made vinyl an even better option for replacement windows.
Weep Hole
Small holes in the exterior sill that encourages water to drain. Generally, manufacturers use weep holes foron lower end vinyl windows.
Related Topics
Construction Terms
Frame Concepts
Installation Terminology
Windsor Window Glossary Of Terms
