Ripping lumber is when lumber dealers will “rip”, or split in two, a piece of lumber to yield two boards from one.
That may be a money-saving option but it is recommended not to use “ripped” lumber structurally.
Lumber grades are assigned considering the number and position of defects (knots, splits, wane, etc.) in the entire piece. For example, a 12-foot 2 x 8 is determined to be a No. 2 grade given a certain number of knots among the full dimension of the piece, both length and width.
Consider splitting that same 2 x 8 in half lengthwise to yield two 2 x 4s. It could very well be that one of the 2 x 4s is left with the majority of the knots, rendering it structurally weak, and therefore, an unknown risk if used structurally. Thus, ripping nullifies the original grade.
Learn more by checking out the SFPA’s Southern Pine Use Guide by clicking here!