The Southern Pine Inspection Bureau (SPIB) handed over expanded and updated design values for visually graded Southern pine that, for the higher grades and wider widths, request smaller cuts in the values than were implemented in June for No. 2 2x4s, the Southern Forest Products Association (SFPA) announced Tuesday.

SPIB's requests now go to the American Lumber Standard Committee (ALSC) Board of Review, which plans to meet on Oct. 18 and consider the request. ALSC is the quasi-governmental board that sets the design value standards for all wood species. Design values indicate how much a piece of wood can be expected to withstand pressures when used in construction. Engineers and designers rely on them to determine, for instance, how far a joist may span or how much weight a truss member can bear.

In January, ALSC reduced design values for visually graded No. 2 Southern pine 2x4s by as much as 30% but declined to change values for any other grades and sizes of the species until testing occurred. SPIB's new report, submitted Monday, contains the results of those tests and the bureau's recommendations. It also suggests a six-month waiting period before the enactment date of any changes.

"The results are encouraging, better-than-expected news for Southern pine lumber producers and users," Cathy Kaake, SFPA's vice president of technical marketing, said in a statement issued by SFPA. (SFPA serves as SPIB's media liaison.) "For example, the impact on joists, rafters, and headers is smaller than originally projected due to smaller reductions for the wider widths commonly used for those applications."

SPIB even suggested a slight improvement in design values for No. 2 2x4s. For example, SFPA said, SPIB suggested that the bending design value increase to 1,100 psi (pounds per square inch) from 1,050, while the modulus of elasticity increase to 1.5 million psi from 1.4 million.

Design values for wood species became headline news last year as a result of concerns beginning years before that, because of the rise of tree farms and shorter growth periods before harvesting, the trees being cut into studs today were weaker than the ones used to set design values back in the 1990s. SPIB investigated, and last year it recommended reduced design values for visually graded Southern pine No. 2 2x4s. Industry associations and trade groups protested the change, arguing that SPIB's action could cause a drop in demand and would devalue whole inventories. Following the ALSC’s rulings, many associations toned down their remarks and tried to find the good in the decision.

While Southern pine has dominated this issue, ALSC also has asked other organizations to test their own species. Earlier this month, the Western Wood Products Association said its tests of Douglas fir and Western Larch found the species have higher bending, tensile, and stiffness properties than when they were last tested in the 1980s.