Table of Contents
There is so much jargon around windows and glazing! This quick guide explains the common terms we use to describe features on a window.
Double Glazing: Refers to two panes of glass in a window frame that are separated by a spacer bar and sealed with air or inert gas in between. This space between the panes of glass helps to insulate the window, keeping the inside of your home warm and the outside noise out.
Glazing Bead: The glazing bead is a small plastic or metal strip that holds the glass in place in the window frame. It is usually secured to the frame with small screws.
Window Cill: A window cill is the horizontal timber, metal or uPVC that runs along the bottom of the window frame. It is used to support the window and provide a level surface for the glass to be fitted against.
Window Head: This is the part of the window frame above the window.
Window Jambs: These are the main vertical parts that form the sides of a window frame.
Glazing Bars: A glazing bar is a bar or supporting strip between adjacent panes of glass. These bars are also known as ‘Muntins’, ‘muntin bars’ or ‘sash bars’.
Georgian Bars: Named after the period in which they became popular, Georgian bars are set inside the sealed unit, which means that they are sandwiched between layers of glazing. Rather than being added to the surface of one single sheet of glazing, they are sealed within the Georgian bar window unit interior to achieve the traditional Georgian design.
Astragal Bars: Yes, more bars! Astragal bars are fixed onto the window’s glazing internally and externally, giving the appearance of Georgian bars (see above!). They separate panes of glass, giving the effect of traditional period features. In other words, astragal bars are applied to one single piece of glazing, but give the effect of multiple panes of glass to enhance the look of the window by giving it this classic ‘georgian’ appearance.
Window Sash: The window sash is the part of the window frame that holds the glass. It is usually made from timber or metal and can either be fixed or sliding.
Weatherstripping: Weatherstripping is a material that is used to seal gaps around windows and doors. It is usually made from rubber or foam and helps to keep drafts and moisture out.