A glazing bar is a bar or rigid supporting strip between adjacent panes of glass. These bars are also popularly known is being called “Muntins”.
Glazing bars are also called “muntin bars”or “sash bars”. Glazing bars can be found in doors, windows and furniture, typically in western styles of architecture. Muntins divide a single window sash or casement into a grid system of small panes of glass.
Until the middle of the 19th century, it was seen as economically necessary to use smaller panes of glass, which were much more affordable to produce, and fabricate into a grid to make large windows and doors. Many considered the division of a window or glazed door into smaller panes to be more architecturally attractive than use of large panes. Hence the window styles that are still popular today. All of these bars can be custom made to meet the requirements of double glazed sash windows.
While glazing bars are more traditional referred to as muntins in sash windows. This can cause confusion, and is often mistaken for ‘mullions’ which is the phrase used to describe the complete separation of two panes of glass.
During sash window restoration we are now able to incorporate double or triple-layer insulated glass to be used in place of single panes in a window divided by muntins or glazing bars. Though this does tend to reduce the effectiveness of the insulation. Insertion of a decorative grid using a variety of different suitable materials, these glazing bars can be sandwiched between two large panels of glass. This won’t improve the heat insulation of your sash or casement windows. It will help to provide more convincing divided light appearance that is often noticed throughout these period property windows. Other options available can involve placing aesthetic glazing bars over a full pane glass window to give the appearance of the glass being separated by glazing bars.