A board foot appears like a hard concept to understand. In reality, it is very simple. Trees are harvested in large quantities in all different sizes. These logs are cut into rough lumber with different widths, thicknesses and lengths. It is not time efficient to group each board type together to determine the quantity. The board foot unit of measure was developed to group these random board types into a volume of measurement to expedite quantity takeoffs and eliminate the need to class each board into a specific width, type or length.

The definition of a board foot is a 1 foot wide by 1 foot long by 1 inch thick piece of lumber. To use this measurement correctly, the definition must be converted to similar units as 12 inch wide by 12 inch long by 1 inch thick piece of lumber or 144 cubic inches of lumber (BF/144 cubic inches). For example, 100 pieces of lumber are cut at 50 pieces at 4 feet long and 50 pieces at 8 feet long with all pieces 24 inches wide and 1 inch thick. How do you tell your distributer the quantity of lumber? You use the board foot of measurement. The 4 foot length members are equal to 57,600 cubic inches of volume (48 inch x 24 inch x 1 inch x 50 = 57,600 cubic inches). The 8 foot length members are equal to 115,200 cubic inches of volume (96 inches x 24 inches x 1 inches x 50 =115,200 cubic inches). The total volume of lumber in cubic inches is 172,800 cubic inches or 1,200 BF (Board Foot: 172,800 cu inches x BF/144 cu inches). This information will be very helpful when ordering you next quantity of lumber or checking your subcontractor on the accurate quantity used on your project. Please reference my webpage at www.RieserBuildingGroup.com for my previous newsletters.