Definition: Dimensional Lumber is lumber that is cut to certain pre-defined sizes. This type of lumber is sawn, planed, and smoothed (though not always smoothed) and ready for building applications.
The most common type of dimensional lumber is the 2x4 (two-by-four). Due to the thickness of the saw, the 2x4 is not 2 inches wide, 4 inches deep but is 1 1⁄2 in × 3 1⁄2 in (38 mm × 89 mm).
Dimensions are only given to the width and depth. Thus, a 2x4 board can be 8 feet long, 10 feet long, 12 feet, and so on, but the length is never figured into the dimensions.
Also Known As: cut lumber, finished lumber
Common Misspellings: lumbar
