Your windows are a crucial part of your home so it pays to learn everything you can about them, including understanding various associated terms. This will also enrich your experience as a homeowner because you’ll be able to easily talk to your window contractor, should anything come up, be it a repair or replacement. To get you started, here is a list of terms you should keep in mind:
Parts of a Window
- Sash – The frame that holds the stiles and the rails, as well as the window glass in place.
- Stiles – Vertical support for the sash frame situated on both sides of a window.
- Muntins – Also called grilles, these are grids on either the inside or outside of a window that divides glass panels for decorative purposes.
- Apron – A horizontal board placed under the stool and is connected to the wall.
- Stool – Also known as a sill, it is located at the bottom of a window, acting like a small shelf.
- Jambs – The side pieces that run vertically to create the window frame.
- Rails – The horizontal counterpart of stiles that hold window glass in position.
- Operator – The lever or crank that enables you to open or close either a casement or an awning window.
- Latch – The device that locks the window and aids in sealing the window to help prevent air leakage.
- Glazing – Window glass; energy-efficiency is best achieved with double or triple glazing.
Popular Window Types
- Double Hung – One of the most popular window types, the double hung window has two operating sashes that can slide up or down inside the window frame.
- Gliding – Also known as a sliding window, this type operates by having one or both sashes slide horizontally to the left or right.
- Casement – This is a hinged window that opens outward by turning a crank. Its hinges can be placed on either the left or right sides of the window.
- Awning – Another hinged window, it opens outward thanks to hinges at the top and the turn of a crank at the bottom.
- Bay/Bow – Bay or bow windows extend outward from the walls of your home, curving out. Bay windows have three panels while bow windows have more, usually four or five.
- Specialty – Windows that do not have the conventional square or rectangular shape. Styles and shapes include circle, pentagon, triangle, chord, leg arch, quarter circle, and more.
Window Glass Technologies
Taking to heart these terms will help you understand window labels better.
- Low-E Glass – A special type of glass featuring low emissivity coating that reduces the level of heat let in without affecting the amount of light that passes through a window.
- Solar Heat Gain Coefficient (SHGC) – The measurement of the amount of solar heat energy that enters the window. A low SHGC means less heat is let in by a window.
- U-Factor – The measurement of heat that is transmitted through a window from the inside. A lower U-Factor means better insulation for your home so less indoor heat is lost.
- Visible Transmittance – The amount of light that passes through a window and is affected by the glazing material, the number of panes, and the window coatings. The higher the VT, the more daylight you have for your space.
Eric Minkiewicz is the President of Huff N’ Puff, a New York-based company that offers replacement windows, doors, gutters, insulation, and roofing services. When he’s not in the field, he shares home improvement tips and other industry knowledge through the company blog.