How to Convert Board Foot to Square Foot
- 1). Measure the width of the wood planks (the narrowest of the wood's three dimensions, the width of the exposed surface), if you don't know it already.
- 2). Divide the number of board feet by the number of inches thick the wood is. This will give you your total square feet exposed.
For example, 20 board feet of wood that is 5/8 inches thick has a surface area of 20 / (5/8) = 20---(8/5) = 32 square feet. Note here that dividing by a fraction is the same as multiplying by its reciprocal. - 3). Check your work by multiplying your answer by the wood's thickness. Continuing with our example above: 32 square feet --- (5/8 inches thick) = 20 (square feet --- inches) = 20 board feet.