# Wood Volume

## How much wood can you expect from your logs?

### Good to Know

• One board foot (BDFT) is 1”x 12”x 12”.
• Kerf is the thickness of the blade cut that produces wasted sawdust.

### Volume Calculation Methods

There are several scales that can be used to estimate the BDFT yield of logs: the Doyle, the Scribner, and the International.

• The Doyle rule was developed by Edward Doyle prior to 1850. This rule tends to be inaccurate in estimating log volumes due overestimating large logs while underestimating small logs.
• J. A. Scribner developed the Scribner Log rule in 1846. It is based on a log diagram of 1” slabs and a ¼” kerf loss. This method does not have allowances for log tapering and thus underestimates the volume of longer log lengths.
• The International scale was originally developed by John C. Clark in 1906 as the 1/8” rule. In 1917 he developed the 1/4” rule, which is the formula used today. This International scale is based on a mathematical formula that accounts for log tapering and a 1/4″ blade kerf.

Of these three, the Doyle rule is the least accurate, the Scribner rule is an intermediate estimator, and the International 1/4” scale is the most accurate.

Because of the thin kerf of the Wood-Mizer mill, there is significantly less waste, which results in yields that exceed all three scales. I use the International 1/4 inch rule for estimating. You can use the table below to estimate the volume of your logs.

 Gross Volume of a log, International 1/4″ Rule. Measure diameter inside bark at small end of log. Read volume in Board Feet. Diameter of log small end Length of log 8 10 12 14 16 18 6 10 10 15 15 20 25 7 10 15 20 25 30 35 8 15 20 25 35 40 45 9 20 30 35 45 50 60 10 30 35 45 55 65 75 11 35 45 55 70 80 95 12 45 55 70 85 95 110 13 55 70 85 100 115 135 14 65 80 100 115 135 155 15 75 95 115 135 160 180 16 85 110 130 155 180 205 17 95 125 150 180 205 265 18 110 140 170 200 230 265 19 125 155 190 225 260 300 20 135 175 210 250 290 330 21 155 195 235 280 320 365 22 170 215 260 305 355 405 23 185 235 285 335 390 445 24 205 255 310 370 425 485 25 220 280 340 400 460 525 26 240 305 370 435 500 570 27 260 330 400 470 540 615 28 280 355 430 510 585 665 29 305 385 465 545 630 715 30 325 410 495 585 675 765 31 350 440 530 625 720 820