- Finger-jointing: A means of joining individual pieces of wood together to form longer lengths. The ends of the pieces are machined to form a set of interlocking fingers, which are then coated with adhesive and meshed together under pressure.
- Fixed: Non-venting or non-operable.
- Flashing: A metal or plastic strip attached to the outside of the head or side jambs to provide a weather barrier, preventing leakage between the frame and the wall.
- French hinged door: Hinged door(s) which have wider panel members around the glass.
- French sliding door: A sliding door which has wider panel members around the glass, giving the appearance of a French hinged door.
- Gasket: A pliable, flexible continuous strip of material used to affect a watertight seal between sash and frame of roof windows much like the seal around a refrigerator door.
- Glazing: The glass panes or lights in the sash of a window. Also the act of installing lights of glass in a window sash.
- Glazing bead: A plastic or wood strip applied to the window sash around the perimeter of the glass.
- Glazing compound: A pliable substance applied between the window sash and the lights of glass to seal against the elements and sometimes to adhere the glass to the sash.
- Glazing stop: The part of the sash or door panel which holds the glass in place.
- Head: The main horizontal member forming the top of the window or door frame.
- Head board: A flat board cut to fit the contour of a bow or bay window and installed between the head jambs and the flat wall surface to finish off that area which would normally be ceiling.
- Header: A heavy beam extended across the top of the rough opening to prevent the weight of wall or roof from resting on the window frame.
- Hopper: A window with a top sash that swings inward.
- Jack stud: Framing members, generally 2" x 4"s, which form the inside of the window or door rough opening. They run from the sole plate to the header, which is supported by them.
- Jamb liner: Metal or plastic covering the inside surface and head jambs of sliding windows.
- Keeper: The protruding, hook-shaped part of a casement window lock, which is mounted on the inside surface of the sash stile.
- Lift: A handle or grip installed on the bottom rail of the lower sash of a double-hung window to make it easier to raise or lower the sash.
- Light: (also spelled lite) Glazing framed by muntins and/or sash in a window or door.
- Low-E glass: A common term used to refer to glass which has low emissivity due to a film or metallic coating on the glass or suspended between the two lights of glass to restrict the passage of radiant heat.
- Low-E Squared glass: Similar to Low-E glass but also greatly reduces the amount of heat gain in the home.
