Actual block opening – not including the buck strips.
(Lock rail) – One of the two horizontal members of a double-hung sash which come together. See: Check rail.
Any structural part of a window or a door, such as a rail, stile, or lintel.
Window sash and other wood products made in a wood-working plant.
Two members joined at an angle, commonly 45 degrees.
Size in width and height are given in feet and inches to even sizes. Some modular sizes use a combination of modular width and commodity heights.
(Vapor barrier) – A material which retards the passage of water vapors from one space to another. Polyethylene sheet is commonly used as a vapor retarder.
Percentage of dry weight of material which is composed of water, such as in wood.
(Molding) – A relatively narrow strip of wood used to conceal a joint or to emphasize ornamentation of a structure.
A slot or rectangular cavity cut into a piece of wood to receive another part.
(Moulding) – British spelling of mold, and molding.
A clip designed to anchor a tube mullion in an opening.
Mullion / Mull
Extrusion that connects two or more windows or doors together in a single opening.
A sash divided into many lites.
A lock with multiple locking points, typically to the head and sill, jamb or astragal.
Exterior and interior extrusions or wood in the sash of a window or door which appear to divide the glass into smaller lites.