30+ Window Terms You Might Not Know

Understanding window terms is a must for any homeowner for several reasons. Whether you are trying to make sense of DIY guides or are wanting to understand what your designer, architect, or contractor is trying to say about your property’s windows.

Aside from that, one of the useful perks of knowing window terms is that you simultaneously get familiarized with the scope of options in the fenestration market.

To make it easier for you, we’ve divided the window terms in this guide based on topics such as:

• Parts of the window
• Types of windows based on the material used
• Types of windows based on style/functionality
• Window terms related to energy efficiency and other features

Let’s begin!

Parts of the Window

1. Frame - This is the part that supports the entire window. It can be made of different materials and is made up of the head, the sill, and the jambs.
2. Head - This is the horizontal section of the window frame that’s located on top.
3. Sill - This is the horizontal section of the window frame that’s located at the bottom.
4. Window nook - Also known as the window bench, this is the seat usually added to projection windows or to deeper windows with a wider sill. It can be as deep as 17 to 22 inches for comfortable seating.
5. Jambs - These are the vertical sections of the window frame on the left and right sides.
6. Sash - This is the moveable part of an operable window.
7. Balance - This is a mechanical device, typically equipped with a spring that is found in hung windows. It counterbalances the weight of the moveable sash.
8. Window lock - This window term encompasses a wide scope of locks used to keep operable windows from opening.
9. Operator - This is a crank that opens and closes both the casement and awning windows.
10. Weatherstrip - This is typically placed in between the sash and the window frame in order to reduce air leaks and help keep precipitation out.
11. Mullion - This is any vertical or structural element that combines a pair of windows or a larger window combination.
12. Grilles - These are decorative pieces to give the illusion that the window has multiple glass panels. Typically, grilles are made of steel, aluminum, or iron and are permanently fixed to the glass.
13. Weep Hole - These are intentional and visible small openings located at the bottom of the window frame to prevent a buildup of water and condensation.

Types of Windows Based on the Material Used

14. Wooden windows – these are windows that have a window frame and sash made of wood. These require regular maintenance to prevent warping, rotting, and swelling.
15. Aluminum windows – these are windows that have a window frame and sash made of aluminum. Without due maintenance, these windows are highly prone to corrosion.
16. Steel windows – these are windows that have a window frame and sash made of steel. Though these windows are stronger than aluminum in terms of rust resistance, they are known to be expensive, heavy, and still prone to airborne salt damage in coastal areas.
17. Fiberglass windows – these are windows that have a window frame and sash made of fibreglass. This durable material is also low-maintenance.
18. Vinyl windows – these are windows that have a window frame and sash made of vinyl. Vinyl is known for its great insulation, chic look, and durability.

Types of Windows Based on Style and Functionality

19. Fixed windows or picture windows – these windows, by design, do not move and are meant to showcase a view or let in more light.
20. Operable windows – this window term encompasses all window types that can open.
21. Single-hung windows – these windows have one movable sash (that can be slid upwards) and one fixed panel at the top.
22. Double hung windows – these windows have two sashes. One is on top of the other but both sashes can move vertically.
23. Single slider windows – these windows have one single sash that moves horizontally and a fixed panel that stays in place.
24. Double slider windows – these windows have two sashes that are arranged side-by-side, and can both move horizontally on a track.
25. End vent slider windows – these windows have 1 fixed panel at the center and two sliding sashes on both ends.
26. Casement windows – these windows have a hinge on the side (like a door) and open outwards from the side.
27. Awning windows – these windows have a hinge on the top and open outwards from the bottom.
28. Projection windows – this window term refers to both the bay and bow window.
29. Bay windows – these windows comprise various window panels to form a projection that is semi-polygonal in shape.
30. Bow windows – these windows have multiple window panels (more than that of projection windows) to form a projection that is curved in shape.
31. Combination windows – this is a window term that refers to windows grouped close together, appearing as a single unit. Typically combination windows have 1 or more fixed windows and 2 or more operable windows. In some cases, they may also be purely comprised of fixed windows.

Window Terms Related to Energy-Efficiency and Other Features

32. ENERGY STAR® symbol – an internationally-recognized mark for products (including windows) that are certified as energy-efficient.
33. Insulated glass unit – also known as IGU or sealed glass, these are made up of two or more sheets of glass on a spacer with argon/krypton/air in between. They are sealed this way for added window insulation.
34. Double glazed windows – these windows have an IGU that has two panels of glass.
35. Triple glazed windows – these windows have an IGU that has three panels of glass.
    
36. Quadruple glazed windows – these windows have an IGU that has four panels of glass.
    
37. Low-E coating – this stands for low-emissivity coating. It reduces the amount of infrared and UV rays that pass through the window, thereby contributing to the window’s insulation and also preventing UV damage.
    
38. Easy-clean glass coating – refers to the window glass coating that helps prevent moisture and grime buildup.
    
39. Stormguard Technology – this is a feature in Clera Windows that protects against blowouts in harsh conditions.

Looking For More Information on Windows?

Clera Windows + Doors is both a leading manufacturer and a thought-leader in the fenestration industry. Our doors and windows have it all: durability, style, and energy-efficiency.

We prioritize making window and door information readily available to help homeowners and property owners with their biggest window/door questions. For a more thorough list of window terms, check out our glossary. You can also check out our blog for more insights and guides on home improvement.