Industry Coalition Offers Solution to Issue of Southern Pine Design Value Changes
Originally published by: SBCA — October 21, 2011
The following article was produced and published by the source linked to above, who is solely responsible for its content. SBC Magazine is publishing this story to raise awareness of information publicly available online and does not verify the accuracy of the author’s claims. As a consequence, SBC cannot vouch for the validity of any facts, claims or opinions made in the article.
At the American Lumber Standards Committee (ALSC) Board of Review meeting yesterday (Oct 20), a strong coalition made up of representatives from SBCA, National Association of Homebuilders (NAHB), NAHB’s Building System Council, the Leading Builders of America, Associated Builders and Contractors (ABC), Truss Plate Institute (TPI) and National Lumber & Building Material Dealers Association (NLBMDA) provided testimony. In representing many of the parties likely to be impacted by changes to Southern Pine Lumber design values, they discussed the potential ramifications of the proposed changes and provided a wide variety of thoughts and perspectives.
Some of the key points raised in the testimony were:
- A key concept is that lumber grade-marks = lumber design values for engineering purposes. Accurate lumber design values are critical to engineers, truss manufacturers, builders, contractors, and other end-users/consumers from an accurate building design perspective.
- End users need to rely upon the expertise of the lumber manufacturers and their grading agencies for lumber design values, and specifically on the design values to use and how to use them.
- Based on all the information available to us historically, from Southern Pine Inspection Bureau (SPIB) and Mississippi State University (MSU), it strongly appears that when plantation stands of timber with large percentages of juvenile wood are turned into structural lumber, they have much lower design values.
- While the SPIB data suggest that the Southern Pine region is producing lumber that has lower design values, this meeting opens the door for a SPIB, MSU and SBCRI data review to more fully understand the data and potentially take advantage of the fact that there are regions and lumber mills that have sources of timber that will provide the same design values used today with the same visual grading procedures.
- If, as SPIB states, the specific gravity can stay the same on average then it points to a sizeable amount of high strength lumber that must still be available in the tested population.
- It was readily apparent through testing that juvenile/pith center/medium grain lumber is obvious and easy to segregate. This seems to be the best and least economically impactful way to resolve the SYP value degrade.
- One reasonable option is to sort out the low strength lumber during a visual grading process, using existing or new technology that the lumber production experts define, and leave the high strength lumber with the same grades, sizes and lumber design values as we are using today.
- The most logical solution for lumber purchasing businesses, industries, and the public is for the lumber industry to change the grading rules in order to give them the lumber design values they thought they have been purchasing all along.
It is clear from the meeting that some action will need to be taken with respect to the SPIB data as it is more fully reviewed and analyzed. Upon completion of a more robust analysis, end-users will need a well-defined and clearly articulated SPIB/SFPA/ALSC/NDS design value implementation plan, whereby those with lumber design value expertise provide specific counsel on what design values end-users like builders and engineers should use to perform structural design during any transition phase. This implementation plan should be backed up with sound, published justification for which design values should be used.
Over the next 60 days, leading up to the next ALSC meeting, SBCA will be working with the coalition members to further analyze existing Southern Pine Lumber test data, and advocate for solutions that account for all stakeholder points of view, is well grounded technically, and makes good sense for the structural building components industry and all end users.
As reported earlier this week, the SPIB and the Southern Forest Products Association (SFPA) recently published notices announcing a potential reduction of grade-marked Southern Pine Lumber design values for all structural end uses (including site built construction and lumber remanufactured products, such as trusses, solid sawn I-joist flanges, header framing, wall framing, etc.).
The ALSC Board of Review initially announced it would review SPIB’s proposed grade reductions of Southern Pine Lumber at its October 20, 2011 meeting. Due to overwhelming feedback from SBCA and other affected parties, ALSC issued a subsequent memo indicating it would delay its decision regarding Southern Pine design values in order to hold an additional hearing in approximately 60 days, and would still convene the October 20 meeting.
SBCA’s position statement, and all related documents, can be read in their entirety on its lumber page. Refer to this web page for ongoing information and analysis of this issue.
A special thank you goes to the following SBCA members who attended the ALSC meeting and provided valuable testimony or input on behalf of the truss industry: Steve Stroder (ProBuild), Joe Hikel (Shelter Systems Limited), Steven Spradlin (Capital Structures), Mike Cassidy (TPI) and Gary Raven (Builders FirstSource). In addition, the following companies have spent a significant amount of time participating in our industry's working group since the beginning of October, and worked on preparing our industry's position: 84 Components, A-1 Roof Trusses, Apex Technology, Clearspan Components, Inc. Eagle Metal Products, ITW Building Components Group, MiTek Industries, Inc., Rigidply Rafters, Inc., Southern Components, Inc., Stark Truss Company, Inc., True House, Inc. dba True Truss, Truss Systems, Inc., Trussway, Ltd., and Universal Forest Products. All the companies listed above have committed significant resources toward protecting and advancting the best interest of the entire industry.