What is a Sash
A sash is the part of a window that holds the glass and framework around the glass in place. Window sashes are fitted into the window frame and may or may not be movable. The sash is made up of the window glass, frame, grille, gaskets and gas. This includes two pieces of glass for a double-paned window and one for a single pane. The frame of a sash could be made out of wood, fiberglass, vinyl or metal. The grille is the mullions or dividers inside the glass, the gasket seals the glass, and the gas inside the panes serves as an insulator. In some rare instances, sashes have been used to create unique looking cabinet doors as well.