ALSC Approves Only SP No. 2 2x4 Design Values, Effective June 1
Originally published by the following source: SBCA — January 11, 2012
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.
The Board of Review of the American Lumber Standards Committee (“ALSC”) today announced that it has approved the Southern Pine Inspection Bureau’s (“SPIB”) proposed design value change for the No. 2 2x4 grade of Southern Pine only. These new No. 2 2x4 design values were approved by ALSC with a recommended effective date of June 1, 2012, which will allow for their orderly implementation. In reaching this decision, the Board of Review did not approve a change in design values for other sizes and grades as recommended by SPIB. The Board of Review further urged SPIB to “proceed with all deliberate haste to complete [additional] testing and analysis at the earliest opportunity.”
What does this mean? As of June 1, 2012 the following design values for 2x4 No. 2 Southern Pine will be as follows:
Based on the ALSC decision, this is the only change that has been made to the Southern Pine Design values table as they currently exist in the marketplace and this change will become effective June 1, 2012. A complete copy of the ALSC written decision is set out below. As the ALSC decision indicates, additional Southern Pine grades and dimensions are currently being tested and additional ALSC decisions are anticipated later in 2012.
Discussions are currently taking place among the leadership in key industry segments to arrive at a united approach or policy with respect to implementation of the new design values for the Southern Pine No. 2 2x4 grade. It is expected that guidance will be sought from the findings and recommendations coming out of the Southern Pine Design Value Forum held in Atlanta in November, 2011. Those findings and recommendations can be found at http://www.sbcindustry.com/lumber.php
SBCA believes the narrow ruling on the part of ALSC and the reasonable implementation date will allow for Southern Pine specifiers and users to effectively plan for a reasonable marketplace transition.
Following is the ALSC Board of Review ruling, which was appended to the minutes of their January 5, 2012 meeting:
AMERICAN LUMBER STANDARD COMMITTEE BOARD OF REVIEW
In the Matter of the Submission of the Southern Pine Inspection Bureau for Approval of Supplement 9.
This matter came before the Board of Review (the “Board”) on the submission of the Southern Pine Inspection Bureau (“SPIB”) for approval of proposed Supplement 9 to the 2002 Standard Grading Rules for Southern Pine Lumber containing revised design values for the major and minor species of Southern Pine (the “Submission”).
The Board notes that the issue of the adequacy of design values for these species was originally raised in anecdotal information from outside parties in 2010, indicating that their testing of some Southern Pine lumber had resulted in breakage below the published values. SPIB developed a sampling and testing plan (the “Plan”) to determine if there were grounds to believe that the resource had changed. The consideration of the Plan followed normal established procedures. The Plan was submitted to the Forest Products Laboratory (“FPL”) for technical review and advice, the matter was noticed on the agenda of the Board’s meeting, the agenda was sent to all members and alternates of the Committee and all other parties that had requested Board of Review agendas. The agenda noted that all background materials were available upon request. The Plan was a statistically appropriate approach based on a random sample of No. 2 2x4 lumber on a production-weighted basis from all producing regions. This Plan was approved by the Board on November 18, 2010.
SPIB and Timber Products Inspection (“TP”) gathered a statistically valid sample and sent pieces for testing of MOE and MOR to the SPIB lab and pieces for testing of MOE and tension to the TP lab. Because of the magnitude of the indicated reductions in the design values based on the No. 2 2x4 testing, SPIB submitted an additional Sampling Plan on September 15, 2011, to evaluate a range of different sizes and grades (the “Matrix”) which the Board approved after consultation with theFPL, notice to interested parties and an open meeting on October 20, 2011. The results and analysis is expected later in 2012.
The Submission was originally made to the Board by cover letter dated September 15, 2011. Because the Board was aware that the Submission was of great interest and concern to affected parties, it conducted a hearing on October 20, 2011 pursuant to Section 10.10 of the American Lumber Standard, Voluntary Product Standard 20-10 (the “Standard”), to allow presentations. Approximately 50 people attended that session. Prior to the hearing, the Board also determined that affected parties should have additional time to review the matter and make submissions. A second hearing was duly noticed and held on January 5, 2012, at which approximately 90 people attended in person and another 25 by phone. All interested parties were afforded an opportunity to provide comments to the Board, in writing and in person or by phone.
In reviewing this Submission, the Board is subject to the provisions of the Standard, including Section 184.108.40.206 which provides in relevant part:
Development of design values – Design values contained in grading rules shall be developed in accordance with appropriate ASTM standards and other technically sound criteria. The National Institute of Standards and Technology, with the advice and counsel of the U.S. Forest Products Laboratory, shall be the final authority as to the appropriateness of such standards or criteria.
NIST has specifically approved ASTM D-1990 – “Standard Practice for Establishing the Allowable Properties for Visually-Graded Dimension Lumber from In-Grade Tests of Full-Size Specimens” as an appropriate standard for developing design values.
D-1990 contains restrictions on the use of data. For example, Section 7.2 provides in relevant part:
Grade – To adequately model grade performance, it is necessary to sample a minimum of two grades representative of the range of grade quality ... Grades sampled to model grade relationships shall be separated by no more than one intermediary grade and no more than one quarter of the total possible range … in assumed bending GQI.
Similarly, Section 7.3 addresses width:
Width – In order to adequately develop the data for width, at least three widths per grade shall be tested, and the maximum difference in width between two adjacent widths shall be 4 in. (10 cm).
As noted above, the current phase of the testing performed by SPIB and Timber Products Inspection involved only No. 2 2x4’s.
The Board is constrained by this controlling authority to decline to approve the proposed design values for grades and sizes of Southern Pine other than No. 2 2x4 at this time. In reaching this conclusion, the Board is mindful that testing is currently underway on a full matrix sample consistent with Section 7.4 of the D-1990. The Board urges SPIB to proceed with all deliberate haste to complete this testing and analysis at the earliest opportunity.
ASTM D-1990 does contemplate the development of design values for a single size and species cell. (See, Section 4.2.) The information submitted on this size and grade did, in the Board’s judgment, comport with D-1990 and applicable statistical principles. These No. 2 2x4 design values are approved with a recommended effective date of June 1, 2012, which will allow for their orderly implementation.
Although given the facts, circumstances and controlling authority of this particular matter, the Board did not approve design values for the other sizes and grades and has recommended a future effective date, it cautions all interested parties to take note of all available information in making design decisions in the interim. The values in the SPIB proposal represent approximately a 25-30% reduction. Many of the critics of the proposal acknowledged that some reductions were in order, albeit the magnitude of those reductions was disputed. All design professionals are advised in the strongest terms by the Board to evaluate this information in formulating their designs in the interim period.
The Board also wishes to commend the Southern Pine Inspection Bureau. The original testing did not contemplate the results that ensued nor was it designed to be a full matrix. Faced with sizable indicated reductions, SPIB felt obliged to expand the scope of its recommendations to other sizes and grades in an abundance of caution and in furtherance of its stewardship of the Southern Pine rules.
In case you missed it on Monday, here are a few key lumber industry related news items that have particular relevance to this issue going forward: