For wooden posts in buildings used for ordinary purposes, when the length in inches does not exceed twelve times the least thickness, the safe strength of the post may be obtained by multiplying its sectional area in square inches by 1,000 for long leaf yellow (hard) pine, 900 for Oregon pine, 800 for spruce or white oak, and 700 for white pine. For machinery or full permanent loads (as a brick or stone wall) these values should be reduced one-fifth.

The safe load for posts whose length in inches exceeds twelve times their least dimension may be computed by means of the following table, allowing four-fifths for Oregon pine, three-fourths for oak and Norway pine, and five-eighths for spruce and white pine of good quality: