New Southern Pine Design Values Set For Review in January 2013

The Southern Pine Inspection Bureau (SPIB) has resubmitted its proposed southern pine design values for visually graded lumber to the American Lumber Standards Committee’s (ALSC). The new design values were originally intended for review during an ALSC Board of Review meeting on October 18. The SPIB withdrew its proposal shortly before the meeting in light of a Forest Products Laboratory (FPL) report of discrepancies.

Since that time, both the SPIB and FPL have cooperated to conduct a final analysis of the numbers. The variations in the initial calculations were attributed to the use of different rounding conventions. In the most recent and final analysis, both agencies reviewed figures made of up more than 300,000 points of data. According to the Southern Forest Products Association (SFPA), this is the largest submitted data set since the initial In-Grade Testing Program was developed in 1991.

Earlier this week, the FPL submitted a report on its review of the SPIB values to the ALSC. The FPL stated it is in agreement with the SPIB that the submitted design values provided an accurate estimate of grade quality index, cell summary information and compression. An estimate for modulus of elasticity is currently underway per the proposed values.

The new design values call for lower values for all lumber 2”x 4” thick and 5”-12” wide. In general, bending, tension parallel to grain and compression parallel to grain all received lower pounds per square inch (psi) values. The only exceptions to this were the No.1 Dense and higher grades (all Select Structural categories), which received higher values for tension parallel to grain. As more details about what the design values will mean for the industry become available, we will continue to update this story.

Along with other industry groups, the SFPA continues to advocate for a six-month period of transition after the ALSC Board certifies the new values. A review of the new design values is on the agenda for the next ALSC meeting at 9 a.m. EST on January 30, 2013. A meeting notice and agenda is available for review on the ALSC website. To get a copy of the FPL report or to attend the meeting, email the ALSC at alsc@alsc.org.