Reduced Design Values for Southern Pine Increase Cost of Building With Wood

The Steel Framing Industry Association (SFIA) recently issued a report that assesses the impact on construction of the downgrade of structural values in Southern Pine – one of the most commonly used species of wood in construction. The result is higher costs in construction and an increase in the competitiveness of cold-formed steel framing.

What Triggered the Change?

The previous design values for Southern Pine were developed back in the 1980s, but the mix of species that make up the grouping of Southern Pine has changed over time.  With a change in mix comes the possibility of a change in performance, so the Southern Pine Information Bureau (SPIB) participated in a test program to collect an expanded set of design values.  The result of that program was an approved set of reduced design values issue January 2013.

What Does It Mean?

The SFIA report includes a Technical Application and Evaluation that reviews the overall cost impact of the decision when applied to a real job.  In the example job the reduced structural values of Southern Pine would mean higher grades of studs are required in several cases.  As a result, the total cost of the framing system in the example analyzed would increase by 5 percent.

The report also raises other legitimate questions based on the findings from the analysis on Southern Pine:

• Have there been similar changes to the resource mix of other wood products that warrant reassessment?
• Will the builders, insurers and consumers accept structures framed with substandard materials while the building codes and standards are changed in their area?

For more information and to view the full SFIA report, visit here.