What Are Those Window Parts Called?
Understanding Window Terminology
This short guide will highlight some of the key window parts and hardware that you should be familiar with when you’re planning on replacing or installing new high-quality windows.
Below are diagrams showing you the different parts of the most common two window designs in the UK market.
The Anatomy Of A Sliding Sash Window
Sliding sash windows (or double hung windows) are one of the most common types of windows present on historic buildings in the UK, especially those of the early 18th and 19th centuries. Let’s have a look at the common window terminology surrounding the sliding sash.

The Main Window Parts
- Frame: There are three components to the frame:
- (1a) Head across the top
- (1b) Side Jambs down each side
- (1c) Sill across the bottom
- Glazing: The glass in a window is called glazing and a range of options are available.
- Glazing Bars: The wood or aluminium clad wood profiles that gives the appearance of subdivision of the glazing
- Top Sash: The upper component of a sash window (Can be fixed or operable)
- Bottom Sash: The lower component of a sash window
- Meeting Rail: The rail of each sash that meets at a horizontal level when both sash parts are close
Hardware Terminology
- Sash Lifts (or Finger Lifts): The small handles at the bottom of the sash that allows you to operate the window with ease.
- Sash Lock: A lock device attached to the meeting rail of the sashes.
- Balance Tubes: The mechanism that allows the window to stay into a desired opening position
- Weighted: A more traditional balance mechanism which features a chord and pulley.
- Spring Loaded: A more contemporary balance mechanism that fits neatly into the building profile and which is invisible to the naked eye.
Find Out More About Marvin’s Sliding Sash Windows
Learn more about the features of Marvin’s finely crafted wood sliding sash windows or low-maintenance aluminium clad wood sliding sash windows below. Click on a window to find out more.
The Anatomy Of A Casement Window
Casement windows are hinged at the side and can come either in pairs or on their own within a window frame. These windows are opened and closed with a crank or push-out handle. Let’s have a look at the main window terminology.

The Main Window Parts
- Frame: Identical to the sliding sash window, there are three components to the frame:
- (1a) Head across the top
- (1b) Side Jambs down each side
- (1c) Sill across the bottom
- Glazing: The glass in a window is called glazing.
- Glazing Bars: The wood or aluminium clad wood profiles that gives the appearance of subdivision of the glazing
Hardware Terminology
- Crank Handle: A crank & turn operational handle that allows for a smooth opening transition.
- Push-Out Handle: A traditional style handle for casement windows.
- Lock Lever :An adjustable lock system installed on the operative panel(s) to enhance security and performance.
- Sash Limiter: A safety mechanism that allows you to safely open your window on a windy day.
Find Out More About Marvin’s Casement Windows
Learn more about the features of Marvin’s ultimate wood casement windows or low-maintenance aluminium clad wood casement windows below. Click on a window to find out more.
Other Window Operational Design Terms
Hover over the following window terms to see the design.
- Awning Window
- Bay Window
- Fixed Window
- Special Shape Window
Still Not Sure What It’s Called?
Contact us today and we’ll be more than happy to help you with any window or door terminology that you’re confused about.