The term refers to lumber that is nominally 1 1/4 inches (1.25 inches) thick. The designation “5/4” is a traditional way of specifying this thickness in the lumber industry. Actual dimensions may be slightly less due to the milling process. For instance, after surfacing, a piece designated as such might measure closer to 1 inch thick. It’s frequently employed where a thicker, more substantial appearance or greater structural integrity is desired compared to thinner boards.
Material of this thickness offers enhanced strength and durability for applications like shelving, stair treads, furniture components, and trim work. Historically, using thicker stock provided a way to achieve desired profiles and visual weight, contributing to the aesthetic appeal and longevity of crafted items. This dimension stock bridges the gap between standard “one-inch” boards and thicker timbers, providing a versatile option for construction and woodworking.