In the United States, the monitoring of the inspection, grading and marking systems for softwood lumber, including finger-joined lumber, is under the jurisdiction of the American Lumber Standards [ALS] Committee and Board of Review. The organization and functions of the ALS are outlined in the American Softwood Lumber Standard, Voluntary Product Standard DOC PS 20-99.
The PS 20-99 standard establishes lumber sizes, grades, species, assignment of design values, and the preparation of grading rules. The standard is prepared in accordance with U.S. Department of Commerce procedures and is implemented through an industry wide accreditation and certification program.
The ALS Board of Review evaluates and certifies the conformity of any grading rules published by lumber rules-writing agencies, such as the National Lumber Grades Authority [NLGA] in Canada, the Southern Pine Inspection Bureau [SPIB], Western Wood Products Association [WWPA], West Coast Lumber Inspection Bureau [WCLIB] and the Redwood Inspection Service [RIS]. The building codes only recognize lumber that has been graded, inspected and marked in accordance with a certified grading rule developed by an accredited rules-writing agency.
Finger-joined lumber must meet the identical requirements found in the grading rules for regular sawn lumber. Grading rules do not consider the presence of finger joints to reduce strength properties. Finger-joined lumber must also meet special product standards on quality control requirements for strength and durability of the joints. NLGA’s Special Product Standards SPS 1 and SPS 3 in Canada or WWPA’s Glued Products Procedures & Quality Control, C/QC 101.97 are examples of these product standards.
Finger-joined lumber meeting these standards is considered equivalent to solid sawn lumber of the same dimensions, grades and species and is recognized by the three major model-building codes and the new International Building Code for such applications. An excerpt, from the 1997 Uniform Building Code (UBC), section 2304.2, attests to the product’s acceptance:
“Approved end-jointed lumber may be used interchangeably with solid-sawn members of the same species and grade. Such use shall include, but not be limited to, light-framing joists, planks and decking.”