Charles Russell, March 21, 2011

I received an e-mail from a developer who wanted to know more about CALGreen’s lumber moisure content requirements. The code stipulates that framing lumber cannot exceed 19% moisture content; however, “green” lumber typically has more than 19% moisture content when stamped at the mill. Any lumber with more than 19% moisture content requires a large connector capacity reduction.

CALGreen’s moisture testing protocol requires moisture readings be taken two feet to four feet from the “grade stamped end of each piece,” which means the infield moisture reading must be taken near the grade stamp label. This is confusing because grade stamped labels are typically not located at the end of the wood members.

With this understanding of CALGreen’s moisture content requirements, here are some questions you may have.
Will a building official accept a certificate that states a lumber company’s lumber contains less or equal to 19%?
I believe building officials will accept such a certificate. The intent of the code and the concern of most building officials is to improve indoor air quality and prevent lumber from being a vehicle for mold and mildew.
Is there a standardized certification method?
There is no standard format for the field reading document or the certificate from the lumber supplier; however, the document must be approved by the local building department. The document should be properly worded to address the intent of the code.
Who can certify the lumber?
CALGreen permits field verifications in three ways: city inspection, installer verification, or third party verification. The local building department determines whether one, two or all three of the verification methods are valid.