Q: What’s the Difference between SPF and SPFs lumber?
A: SPF is short for Spruce-Pine-Fir, a grouping of various commercially important species. SPFs is also Spruce-Pine-Fir, but the lower case “s” indicates that the lumber was produced from logs harvested in the USA, south of the Canadian border. Lumber without the lower case “s” indicates that the log source was exclusively Canadian in origin. The “s” designation became necessary to distinguish the two species groupings as a result of separate testing by the U.S. and Canada.