Apr 13, 2009

Board Feet

Measuring Board feet

When it comes to buying solid lumber it’s a good idea to know how they are going to charge you. This way you have a good idea on what it will cost and there shouldn’t be any surprise when they give you your total.

Simply put, break down all measurements into inches. Then multiply Length X Width X Height. Then divide by 144 (square inches in one board foot)

Dimensions are strictly for rough sawn lumber. So a ¾” pland board is actually called a 1 by.

Example - 1” x 8” x 10’ of red oak

1” is ok.
8” is ok.
Convert 10’ * 12” = 120”
120 x 8 x 1 = 960 sq\in
960” / 144 = 6.66 Board feet

I found a nice calculator that makes this formula simple, all you do is enter the dimensions of the lumber. http://www.csgnetwork.com/boardftcalc.html

So if they charge say $6.00/ board ft. this one piece of 1” x 8” x 12’ would cost$39.99

Unlike softwoods, which are sold in standardized dimensions, hardwoods are sold in random widths and lengths. So to tell how much wood hardwood boards contain, they are measured in board feet. "Board Feet" is a volume measurement. One board foot equals 144 cubic inches. Often, a board foot is illustrated as a board 1"-thick x 12"-wide x 12"-long, but you'll rarely find lumber in those dimensions.

Any board containing a total of 144 cubic inches of wood equals one board feet, regardless of its proportions. To calculate the number of board feet in a piece of lumber, multiply the board's thickness by its width, then its length, all in inches. Then divide by 144: (thickness x width x length)/144

For example, a 1" x 9" x 96"-long board equals six board feet (1x9x96=864/144=6). If this board were 1-1/2"-thick, it would contain 9 board feet (1.5x9x96=1296/144=9). Thinner stock is not typically described in board feet.

Also, hardwood thickness is expressed differently than softwood -- in quarters of an inch. A 4/4 (say "four-quarter") board is 1"-thick. A 1-1/2"-thick board is expressed as 6/4. This often reflects the rough-sawn thickness. Surfaced lumber will be slightly thinner.

Author:
Frankie Talarico Jr.
www.getneds.com