Mechanically graded lumber is lumber that has been tested and evaluated by a machine rather than by visual inspection. While most lumber is visually inspected and graded, machine grading is a more efficient volume service and creates cost-competitive products, while differentiating the higher strength lumber materials. It is commonly used to deliver materials for more demanding applications. Two types of machines are used to grade lumber, machine-stress rated (MSR) lumber and machine evaluated lumber (MEL) machines.

工程木材料是利用股，颗粒，纤维的产品，和木皮，以生产一系列不同类型的产品。Readily available at lumber yards, these products are cut to length in the field, similar to dimensional lumber. The application of engineered wood products is also similar to that of dimensional lumber; however, each offers its own performance and manufacturing advantages. Engineered wood products also have some disadvantages in comparison to dimensional lumber. They have less fire resistant, require more energy to manufacture, have adhesives that can potentially release toxins into the environment, and are prone to moisture damage. Engineered wood products are often used as columns, beams, girders, joists, purlins, rafters, studs and bracing.