Glossary of Door Terms
Astragal: A T-shaped Molded strip that is applied to the stile of the inactive door in a double door set. Its function is to receive the active door and form a weather seal. Flush bolts are secured within this astragal top and bottom.
Base Block: Fits at both sides of a jam to receive the case molding on one side. Traditionally used as decorative detail to which you can butt a larger base molding.
Brick Mold: A trim applied to the exterior edge of the frame and fascia concealing the shim space.
Casing: Trim which covers the joint between windows or door jambs and the surrounding wall surface.
Cripples: Short studs above or below a rough opening to a window or door; they support the rough sill and header.
Divided Lites: Door panes separated by muntins.
Dowell Joint: The use of cylinder shaped pieces of wood to secure the stile and the rail together.
Elliptical Transom: A stationary window above doors which is half oval shaped.
Frame: Parts that enclose the door. They are attached to the wood members lining the rough opening. Also referred to as jambs. Usage: Vertical frame members are called "side jambs," the top horizontal piece is the "head jamb" and the bottom horizontal piece is the "threshold."
Fully Bound: Usually refers to sidelites that have their own jamb system, independent of the door jamb.
Glass Stop: A strip of wood that retains glass within its sash.
Glazing: Glass or other transparent materials used for windows; also the act of installing the glass.
Head Jamb: The top, horizontal member of a window or door frame.
Header: The horizontal wood member that forms the top of the rough opening for a window or door; it supports the wall above it.
Hidden Stucco Mold: A molding applied to the exterior surface of the rough opening, keyed to receive plaster. This allows for installation of the finished unit after plastering is complete. It will be concealed by an exterior finish trim piece.
Lamination: The gluing together of two or more pieces of wood to form a single component (i.e. Laminated stile, 5 pieces glued together for stability warp resistance.).
Lite: A unit of glass in a window or door; it is enclosed by the sash or by muntins; also called pane.
Mortise and Tenon Joint: Rail ends are trimmed (tenoned) in a fashion to be received by the mortised (grooved or boxed) stile.
Mullion: The vertical joint between door and sidelites.
Mullion Cover: A strip of wood applied to the joint between the door jamb and the transom jamb.
Muntin: T-shaped parts secured within stiles and rails that hold panes of glass.
Plaster Mold: A trim secured to the exterior edge of a frame with a grove or "key" edge to receive plaster.
Plinth: A usually square block that forms the corner between side and head casing. It is often carved or turned. Also referred to as corner block.
Pre-assembled Unit: All components of the entry, including doors and sidelites, are precisely sized and assembled at the factory to allow for maximum ease of installation.
Pre-Hang: The pre-assembling of doors within an assembled jamb framework for convenience of jobsite installation.
Radius Transom: A stationary window above doors with a head member that forms a radius, but not a complete half round. This transom requires "legs" on either side.
Rail: Horizontal member of a window or door. (Top rail, lock rail, and bottom rail.)
Reveal: The margin visible between the door jamb and case molding, typically 1/4".
Rough Opening: An unfinished opening where a window or door will be installed. Usage: Rough openings are lined by wood members; the top one is the "header" and the side ones are the "trimmers."
Round Top Door: Forms a complete half circle radius of both door and jamb.
Round Top Transom: A stationary window above the door that is shaped in a half circle.
Sash: The framework holding the glass in a window or door.
Shims: Wedge shaped pieces of wood used between frame and rough opening to adjust and stabilize a door or window system.
Stile: The vertical member of a window or door.
Stop: Trim which prevents a door from moving inside the jamb. It is applied to one side of an interior door frame and the interior side of a transom and sidelite jambs.
Transom: A window directly above a door or another window.
Weatherstrip: A strip of material that covers the contact point between the door and the door jamb. It is designed to prevent water and air leakage.