Trade groups for lumberyards and makers of building components sounded the alarm Wednesday over a proposal to rate visually graded Southern pine, a mainstay in American construction, as being up to one-third weaker by some standards than it currently is regarded. If approved, the changes could force builders, remodelers, and architects to reduce the maximum spans for joists and rafters they had planned to build with Southern pine, buy higher, more expensive, grades of Southern pine, buy other species of wood, or perhaps even shift to different construction materials.

The hubbub revolves around two groups: the Southern Pine Inspection Bureau (SPIB), which is responsible for developing standards involving that species, and the American Lumber Standard Committee (ALSC), a quasi-governmental agency authorized to set grading and quality standards for all lumber used in residential and commercial buildings. But the issues arising now also could end up encompassing many other types of popular framing lumber at a time when both the industry and the U.S. government are pushing to increase wood's popularity as a construction material.

At issue are "design values," the properties that builders can count on Southern pine delivering when they use it in construction. Among those design values are the wood's load values--its ability to resist bending, tension, and compression, as well as the product's general stiffness. Earlier this month, SPIB submitted to ALSC a set of proposed new design values that in four out of seven values are 20% to 35% lower than the old ones. The other three values remain unchanged. (The Southern Forest Products Association (SFPA), an information agency, has written a Q&A summary of the proposal, plus a news release with more background information.)

The ALSC's Board of Review will meet on Oct. 20, and it is expected to discuss the idea then. If it approves the proposal, SPIB then would be free to update the design values.

It's not easy to estimate the change's potential impact on the construction industry, because the proposal affects just one type of wood and because the changes exempt Southern pine products graded by machine (roughly 2% of all production). But the National Lumber & Building Material Dealers Association (NLBMDA) and the Structural Building Components Association (SBCA) both are worried.

"NLBMDA is very concerned that this proposal, unfortunately timed as the economy and housing market struggle toward recovery, offers no phase-in period or implementation strategy to dampen any detrimental impact on the already depressed building market," the association said in a notice distributed Wednesday. "We are also concerned with the extremely limited amount of time the marketplace has been given to anticipate the upcoming Board of Review decision and its impact. ... [T]he outcomes, if not mitigated, could include:

Possible stoppage and delays to thousands of single-family, multi-family and commercial construction projects directly resulting from a publication of new design values for Southern pine;

Re-designs of buildings, units of buildings, and entire projects resulting directly from the publication of new Southern pine design values; and

A significant reduction in the economic value of the Southern pine lumber inventory for dealers, component manufacturers, and builders."

SBCA had essentially the same reaction in its analysis of the proposal.

If approved, the new design values also could reduce the value of Southern pine inventories at lumberyards and distributors because the visually graded lumber that dealers have in stock automatically would get ascribed to it the new design values as soon as SPIB publishes them. As SFPA's summary of the proposal gently put it: "Existing inventory can still be used, but it may need to be used differently."

SBCA and NLBMDA both complained about being caught unawares by the news. "SBCA finds it implausible that the lumber design value reductions now being suggested by SPIB occurred without previous warning or notice of some type as they were responsible for monitoring lumber properties," the Madison, Wis.-based association declared. "... The obvious question that needs an answer is: Are we to conclude that a 2x4 with a load resisting value of 1,500 per square inch changes almost overnight to a value of approximately 1,000 psi?"

"NLBMDA is also deeply concerned about the lack of communication from the inspection bureau about the testing that was clearly underway for many months that could lead to the revision of design values," the Washington-based dealer group said. "The Oct. 3 notice by SPIB that it was submitting the proposed revisions to the ALSC Board of Review for consideration on Oct. 20 creates legitimate concerns that we feel should be addressed now as a way of bringing transparency and accountability to this issue. The lack of leadership on this issue leaves far too much ambiguity and uncertainty in the marketplace."

Emotions run high on this issue for several reasons, in part because they touch on concerns about wood's value as a building material at a time in which the industry has been organizing itself to promote the product and in which the U.S. Department of Agriculture has launched an initiative to promote wood as a green building material. Those pro-wood efforts run against a concern that the increased harvesting of younger, smaller trees in recent decades has resulted in products that might be unable to perform at standards last set in 1991, when older, bigger trees provided more of the harvest. Dealers also complain regularly about grade inflation--what they say is a trend toward wood whose qualities might have meritied a lower grade in years past receiving a higher grade today. While grades often involve the wood's appearance, they also are tied to design values.

In addition, while SPIB's proposal is getting the attention, SFPA's summary notes that SPIB is only the first to submit new values. "Rules-writing agencies responsible for other species are in different stages for evaluating design values," the association said. This implies that the design values of other species also could get reviewed and, possibly, downgraded. Spokesperson for groups representing timber mills in Northeastern and Western states weren't immediately available for comment.

In the meantime, SFPA began taking steps to calm potential fears over the changes. "The strength and superior treatability of Southern Pine lumber against decay and termites continues to provide a great value for manufacturers, designers, builders and consumers," SFPA president Adrian Blocker declared.