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AIR DRIED-Wood dried without application of artificial heat.
BOARD FOOT-A system of measurement. The standard board foot is I in.
thick by 12 in. wide by 12 in. long, but any combination of
dimensions yielding an equivalent amount of wood counts. Board feet are rounded to
the nearest foot and are based on the thickness of
the wood before surfacing. Lumber less than I in. thick is counted as I in.
CLEAR-FACE CUTTING-A board with one
clear face (ordinary season checks permitted) and a reverse side that is sound.
CUTTING-A piece of wood free of knots or other
defects. It can be obtained by crosscutting or ripping, but not by making diagonal cuts.
HARDWOOD-Lumber from any tree with broad leaves
usually shed in the fall (deciduous). Many hardwoods are not that hard. Poplar and willow,
for example, are generally softer than pine.
HEARTWOOD-The darker section of wood extending from
the pith, or center of a tree, to the sapwood. Unlimited amounts allowed in most wood
grades.
KILN DRIED-Wood dried with
artificial heat in a kiln.
LINEAR FOOT-A system of measurement in which only the length of the lumber is
considered. This method is often used in home centers and similar outlets that mostly
market pine.
MOISTURE CONTENT-The amount of moisture trapped in the cells of the wood.
Moisture levels for air-dried wood vary according to region. In Arizona, air-dried
hardwood may reach 6 percent, in New England about 12 to 15 percent. Generally, hardwoods
in the U.S. are dried to 7 to 9 percent moisture content.
SAPWOOD-The growth section near the outside of the log that is generally paler
in color than the center. Unlimited amounts allowed in most wood grades.
SEASON CHECKS-Lengthwise separations resulting from stress as wood dries.
Season checks usually don't affect grade if they will dress out at standard surface
thicknesses.
SOFTWOOD-Lumber from needle-leafed trees, usually evergreens that bear their
seeds in cones (coniferous).
SOUND CUTTING-A section of wood free of rot, pitch, shake, and wane. Sound
knots, worm holes, and several other defects are allowed.
STAIN-Describes the initial stages of decay in hardwoods. Not usually allowed
in most grades unless it will dress out when wood is surfaced to standard thickness.
SURFACE 1 EDGE (S1E) or SURFACE 2 EDGE (S2E)-Rough or surfaced lumber dressed
on one edge (SlE) or two edges (S2E). Nominal width can be 3/8 in. scant of specified
width in lumber less than 8 in. wide, and 1/2 in. less than nominal width in lumber 8 in.
or wider.
SURFACE 2 SIDE (S2S)-Surfaced both sides
THICKNESS-Hardwoods are usually measured according to 1/4in. units of
thickness, referred to as quarters. A rough-sawn 4/4 (four quarter) equals 1 in., 6/4
equals 1 1/2 in., 8/4 equals 2 in., and so on. Most 4/4 is cut about 1 1/8 in. and planes
down to 3/4 in. or 13/16.
Information derived from materials provided by National Hardwood Lumber Association,
Southern Pine Inspection Bureau, Educational Lumber Co., Steve H. Wall Lumber Co.-D.B. |
