Calculating Board Feet
Being able to calculate board feet is helpful when ordering or buying wood so you know what you are paying, or should be paying for a given amount of material.
It can also be helpful when figuring out how much of a specific type or size of wood is needed for a project.
Keep in mind that most sellers round up at least the actual thickness. Say you have a 3/4"-thick piece of dimensioned lumber. For these calculations, it is 1"-thick. The same happens to 7/8"-thick rough lumber which also is calculated using a 1"-thickness.
For the most part, the actual width and length are used to determine board feet but if a price looks odd or is more that your calculations come up with, ask how the seller arrived at the board feet. You might be surprised.
The most common formula uses the thickness and width in inches and the length in feet. For example, a 1" by 6" by 5-feet long equals 2.5 board feet.
1" X 6" X 5' / 12 - 2.5 board feet
You can also use inches in place of the "foot" dimension. This is common when buying rough-cut hardwood but you might see it anywhere eventually.
Figuring that same 1" by 6" by 5-foot long piece of wood would look like this:
1" X 6" X 60" / 144 = 2.5 board feet.
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