Jack Rafter to Lumber Types
Jack rafter. A rafter that spans the distance from the wall-plate to a hip, or from a valley to a ridge.
Jamb. The side and head lining of a doorway, window, or other opening.
Joint. The space between the adjacent surfaces of two members or components joined and held together by nails, glue, cement, mortar, or other means.
Joint cement. A powder that is usually mixed with water and used for joint treatment in gypsum-wallboard finish. Often called "spackle."
Joist. One of a series of parallel beams, usually 2 inches in thickness, used to support floor and ceiling loads, and supported in turn by larger beams, girders, or bearing walls.
Kiln dried lumber. Lumber that has been kiln dried often to a moisture content of 6 to 12 percent. Common varieties of softwood lumber, such as framing lumber are dried to a somewhat higher moisture content.
Knot. In lumber, the portion of a branch or limb of a tree that appears on the edge or face of the piece.
Landing. A platform between flights of stairs or at the termination of a flight of stairs.
Lath. A building material of wood, metal, gypsum, or insulating board that is fastened to the frame of a building to act as a plaster base.
Lattice. A framework of crossed wood or metal strips.
Leader. See Downspout.
Ledger strip. A strip of lumber nailed along the bottom of the side of a girder on which joists rest.
Light. Space in a window sash for a single pane of glass. Also, a pane of glass.
Lintel. A horizontal structural member that supports the load over an opening such as a door or window.
Lookout. A short wood bracket or cantilever to support an overhang portion of a roof or the like, usually concealed from view.
Louver. An opening with a series of horizontal slats so arranged as to permit ventilation but to exclude rain, sunlight, or vision. See also Attic ventilators.
Lumber. Lumber is the product of the sawmill and planing mill not further manufactured other than by sawing, resawing, and passing lengthwise through a standard planing machine, crosscutting to length, and matching.
Lumber, boards. Yard lumber less than 2 inches thick and 2 or more inches wide.
Lumber, dimension. Yard lumber from 2 inches to, but not including, 5 inches thick and 2 or more inches wide. Includes joists, rafters, studs, plank, and small timbers.
Lumber, dressed size. The dimension of lumber after shrinking from green dimension and after machining to size or pattern.
Lumber, matched. Lumber that is dressed and shaped on one edge in a grooved pattern and on the other in a tongued pattern.
Lumber, shiplap. Lumber that is edge-dressed to make a close rabbeted or lapped joint.
Lumber, timbers. Yard lumber 5 or more inches in least dimension. Includes beams, stringers, posts, caps, sills, girders, and purlins.
Lumber, yard. Lumber of those grades, sizes, and patterns which are generally intended for ordinary construction, such as framework and rough coverage of houses.