Parts of a Wood Window

Sashes, Rails and Stiles

• A traditional wood window has two halves. The upper half is called the top sash, and the bottom half is called the bottom sash. These are rectangular panes that contain the glass material. Rails form the top and bottom edges of a sash, and stiles form the left and right edges of a sash. If a double hung window can be opened, the bottom sash is the part that slides upward behind the top sash. The part where two sashes meet is called the meeting rail or check rail.

Frame

• A wood window must be installed into a cutout space in the wall of a home. The frame is formed by wood on all sides and is referred to as the jamb, just as the border for a door is called a door jamb. At the base of the window jamb, another piece of horizontal wood placed below the jamb is the window sill. Some wood sills extend enough from the exterior and interior of the home to be considered shelves.

Muntins and Lites

• Glass window panes in a wood window are called lites. They are held together by putty or metal glazing points. A closer look at the sealing between the lites reveals the presence of more wood. Each horizontal or vertical piece that separates lites is another window part called a muntin, a muntin bar or a sash bar. In old wood windows, glue or nails were used to keep muntins in place, or pieces of glass were wedged snugly with muntins inside the rails and stiles.