Southern Pine Potential Design Value Reductions - Impact on Light Frame Construction Market

Originally published by: SBCAOctober 13, 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.

On October 11, 2011, SBCA distributed recent communications from the Southern Pine Inspection Bureau (SPIB) and the Southern Forest Products Association (SFPA) about the potential reduction of grade-marked Southern pine lumber design values for all structural end uses.

Since then the American Lumber Standards Committee (ALSC) has also sent a notice about the topic and its upcoming meeting on October 20, 2011.

SBCA’s position statement, and all related documents, can be read in their entirety on its lumber page, and a few key points follow.

Since 1924, the light frame construction industry has followed a standard design practice to safely construct buildings. This practice consists of builders, specifiers, and building designers (i.e., architects and engineers) using and/or specifying structural lumber in appropriate applications to resist building code defined loads. Such designers make their lumber end use decisions based on the design values assigned to the grade-marked lumber as applied by the lumber producers through their visual grading procedures. The light frame construction industry is built upon the foundation that load resistant framing design can be undertaken with confidence in the structural reliability provided by those assigning design value properties to each unit of lumber produced.

When Southern Pine lumber producers provide a grade-mark on lumber, the grade-mark that is utilized establishes the set of design values that exist and the capacity of that lumber to resist loads. Neither users nor designers of Southern Pine can be expected to anticipate or define for themselves either a higher or lower design value for the lumber selected and build or design with a value other than what has been published by SPIB.

More importantly, should lumber design values change in a material manner, it is reasonable to expect the entire lumber producing industry, including their grading agencies and NDS, would immediately respond with transition guidance for the end user action(s) to take that would correspond with the changing lumber design values.

The unintended economic impact to designers, lumber remanufacturers such as the members of SBCA, and contractor and builder end-users might very well become significant. These include but are not limited to:

  1. 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;
  2. Buildings, units of buildings, and entire projects that may have to be re-designed directly relating to the publication of new Southern Pine design values;
  3. A significant reduction in Southern Pine lumber inventory economic value overnight for component manufacturers, lumber yards, builders, and homeowners; and
  4. An inadequate supply of Southern Pine lumber with sufficient design properties to meet the growing construction demand for use in roof and floor trusses (and roof rafters and floor joists) and wall panels and conventionally framed walls by builders and contractors who prefer to construct with Southern Pine.

Project stoppage and delays or the cost of the needed re-design to ensure the building code expected level of safe performance could also very well impact the employment of hundreds of thousands of site construction workers and those companies who supply site construction. Project stoppage and delays will result in huge economic losses to project owners, contractors, subcontractors and suppliers who are ill-prepared to absorb further losses from an already dismal construction marketplace. 

For component manufacturers, there is value in immediately communicating with your customers how the potential changes may directly affect each business transaction, now and in the future.