In British Columbia, spruce species, including Sitka spruce, account for 22% of the total forest inventory. Of this, white spruce makes up the largest portion. White spruce and Engelmann spruce (interior spruce) are graded in the single-species group (spruce-pine-fir or SPF) along with lodgepole pine and subalpine fir. Kiln-dried SPF lumber is used as a structural framing material in all types of residential, commercial, industrial and agricultural building applications. The wood of white spruce (Picea glauca) and Engelmann spruce (Picea engelmannii) cannot be differentiated visually. Engelmann spruce wood is slightly denser, harder and stronger than that of white spruce, but the differences are very minor.
White spruce wood is highly valued for lumber, plywood and pulp production. It is used in building construction (framing, sheathing, roofing, sub-flooring), general millwork, interior finishing, furniture components, interior wall paneling, boxes and packing cases. Spruce is used in the manufacture of modular houses, trusses and other structural components that specify kiln-dried Spruce-Pine-Fir wood. It is also used in the manufacture of medium density fiberboard (MDF), paperboard and felt, and it is a major species used in softwood plywood.
White spruce and Engelmann spruce are produced predominantly as SPF lumber in structural grades according to National Lumber Grades Authority (NLGA) rules for dimension lumber. Select Structural, #2 and better, and stud grades are the most common grades produced. As lumber, spruce is extremely versatile because of its high strength to weight ratio.