Kudos to Miles Conway, executive officer of the Santa Fe Area Home Builders Association, for bringing to near-fruition the culmination of efforts begun almost 15 years ago. Soon, vigas will once again be allowed to support New Mexican roofs.
Conway is hosting a lunch Feb. 2 at the association’s offices to present accomplishments by key individuals who worked to bring about the long-overdue acceptance.
Nothing would have been possible without Rachel Wood, a New Mexico forestry professional, who went after and received grants from the U.S. Department of Agriculture. The grants provided for two distinct but complementary pursuits.
One grant allowed her to create something called Source Verified Good Wood. The other funded work by the national labs at Los Alamos and Sandia. Their engineers devised the first-ever round-log roof span charts based on scientific data.
Homegrown span charts were used for many years prior to work by the labs. They were trusted by viga-sellers, builders and code inspectors. But in 2004, New Mexico adopted residential building codes with language from national codes that said if a viga wasn’t graded and stamped by certified lumber graders, it couldn’t be used to support a roof.
Unfortunately, New Mexico didn’t, and doesn’t, have any lumber graders. Furthermore, no national standard exists establishing a consensus on grading peeled softwood logs for structural integrity.
Thus, the need for engineering from the labs.
A second concern was the inability of sustainably harvested New Mexico logs to be given proper respect. Residential green-building certification programs reward projects using wood from forests certified by Forest Stewards Council or Sustainable Forestry Initiative.
Unfortunately, no forests in New Mexico — public, private or tribal — have ever sought the expensive certifications. And yet, all New Mexico forests practice responsible harvesting equal to or better than nationally recognized programs. Thus, the need for a certification program that tracks the sustainability chain of custody, from chain saw to homebuilder. Rachel Wood’s Good Wood program does that.
New Mexico has a residential sustainability certification protocol called Build Green New Mexico. Since 2007, it has been used to certify thousands of homes seeking the state’s popular and generous Sustainable Building Tax Credit.
Roughly patterned along criteria in the National Green Building Standard, it deviated somewhat by narrowing the scope to focus on energy and water conservation and indoor air quality. Unlike national programs, it offered no credit for use of sustainably harvested wood products. Now, because of the Good Wood program, that is set to change.
The devastating fires from summer rendered thousands of acres of trees to fall over and rot, or to be harvested as a building material and carbon-sink. Had responsible thinning been historically employed with sustainable logging practices, damage may have been limited.
Forestry professionals suggest any log skinnier than 16 inches in diameter is appropriate to remove from the forests. That is a big viga. A typical New Mexico ceiling viga is less than 12 inches and as small as 6 inches in diameter — exactly what needs to be thinned to mitigate wildfire.
At the homebuilder’s lunch Feb. 2, open to the public and on Zoom, Rachel Wood will explain how Source Verified Good Wood works. Steve Hale, executive director of Build Green New Mexico, will show builders how using Good Wood products earn points in the protocol, and Conway will update on progress getting viga span charts back into New Mexico residential building codes.
