BAR: A generic term for all horizontal or vertical window or door components that divide the visible glass of a basic unit into multiple lites. Examples would be divided-lite muntin bars, exterior and interior thermal bar muntins, or grille bars.
CHECK RAIL: On a double-hung window, the bottom rail of the upper sash and the upper rail of the lower sash, which meet when the window is closed.
CLAD: A designation given to products whose exposed exterior surfaces are sheathed with aluminum to provide a more durable, low-maintenance surface.
DIVIDED LITE: The division of the sash glazing into multiple individual panes. These divisions are separated by muntin bars.
FRAME: Outer components of a window unit (side jambs, head jamb and sill) that enclose the sash.
GLAZING: Either the act of inserting glass into windows or doors or a reference to the glass in a window or a door.
GRILLE: Removable wood dividers made to simulate divided lites. They fit on the inside of the sash against the glass surface.
HEAD: The upper horizontal member of the frame.
JAMB: The pieces of a door or window frame.
LITE: Term used to describe a single opening in a window or door, occupied by a single piece of glass.
MUNTIN: Wooden bars separating the lites of divided-lite windows.
SASH: A wood perimeter around the glass, which allows some independence from the frame. The sash consists of stiles, the vertical sides of the window sash; and rails, the horizontal sides of the sash.
SILL: The horizontal member which forms the bottom of a window or exterior door frame.
WEATHER STRIPPING: A strip of resilient vinyl, plastic or foam material designed to seal the sash and frame members in order to reduce air and water infiltration.