Since initial development in the 1960s, machine graded lumber has been used primarily in engineered wood products. Metal plate-connected wood trusses, wood I-beams, and glued-laminated timber are three examples. Some engineers and architects use machine graded lumber directly in framing applications to take advantage of its higher stiffness and strength properties.
The Cost-Savings Niche
With its more precise grading and daily quality control testing, machine-graded lumber allows the designer to comfortably utilize full design strength to minimize expensive overbuilding. Thus cost savings result by specifying the optimum lumber grades and sizes in a truss for a given span, or in some cases by substituting smaller sizes, such as a 2×8 machine grade for a 2×10 visual grade in direct framing applications.
Growth on the Horizon
The production volume of machine graded lumber has grown by over 50% since 1990, to approximately 1.1 billion board feet in 1997, or about 2% of total North American lumber production. As machine-graded lumber becomes more available, engineers and architects will undoubtedly specify it directly as they find new and innovative uses for the product. With their efficient use of the forest resource, MEL and MSR lumber will evolve in the coming years, extending the use of lumber and adapting to changes in timber design.
Information in this section comes from Wood Design & Building #7 by authors: Helen Griffin, Dave Gromala, Tom Rogers and Ross Theilen
For more information:
MSR Lumber Producers Council
Anna L. Stamm, Business Manager
6300 Enterprise Lane
Madison, WI 53719
Tel:  848-5339
Fax:  212-5110