F2M Market Watch

New Southern Pine Design Values Approved
Posted on February 25, 2013 by LeAndra Spicer

On January 31, the American Lumber Standards Committee (ALSC) Board of Review unanimously approved the new southern pine design values previously submitted by the Southern Pine Inspection Bureau (SPIB). The new values were rescheduled for review in January after the SPIB withdrew its initial proposal in light of Forest Products Laboratory’s report of discrepancies back in October. The newly approved values will apply to all grades and sizes of visually graded Southern Pine dimension lumber and are set to take effect on June 1.

During the meeting, Kirk Grundahl of the Structural Building Components Association expressed concern over a portion of the proposed language found in Appendix A, which provided information on the derivation of design values. The SPIB agreed to remove the sentence, “Designers of wood structures….and grade grouping” from Appendix A. The Board approved the SPIB proposal with the amended language in place.

As reported in a previous update to this story, the new design values call for lower values for all lumber 2”x 4” thick and 5”-12” wide, with the exceptions of No. 1 Dense and higher grades in Select Structural categories, compression parallel to grain, tension parallel to grain and bending, which received lower pounds per square inch (psi) values. Higher psi values for tension parallel to grain were applied to the No. 1 Dense and higher grades.

The June 1 effective date should allow time for an orderly transition to the new design values.

The SPIB has published the new design values in Supplement 13 to the Standard Grading Rules for Southern Pine Lumber, 2002 Edition, as well as the new span tables. These are available online at Southern Pine, which is provided by the Southern Forest Products Association.



Leave a Comment

*Required







Contributors:

Bob Bratton
Javon Carter
Joe Clark
Peter Coutu
Gordon Culbertson
Mike Fiery
Suzanne Hearn
Sam Houston
Suz-Anne Kinney
Stan Parton
Matt Perkowski
LeAndra Spicer
Pete Stewart
Daniel Stuber
Yang Wan