Full-scale fire resistance tests on wood-frame wall assemblies carried out by the wood industry in 2006 demonstrated that end-joined (finger-joined) studs may not perform on par with equivalent solid-sawn studs, as had long been accepted by Canadian and U.S. building codes. The test results were found to vary significantly with the type of adhesive used, and more importantly, walls constructed with finger-joints made with some adhesives did not exhibit expected fire-resistance ratings. Although no problems have been reported with fire performance in the field, the wood industry quickly moved to address this issue in order to ensure the continued safety of wood structures constructed with these products.
In February 2007, the American Forest & Paper Association (AF&PA) released a qualification procedure for adhesives to be used in fire-rated assemblies that is based on full-scale ASTM E119 fire resistance tests. In 2008 this test procedure was separated into two methods and published as two ASTM standards. These ASTM procedures have since been adopted by both the American Lumber Standard Committee (ALSC) and the Canadian Lumber Standards Accreditation Board (CLSAB).
Although the full-scale test is now accepted as a methodology to qualify adhesives for use in fingerjoined HRA (heat resistant adhesive) lumber, there are obvious advantages to developing a small-scale test procedure for use as an alternative to the full-scale procedure. This project worked to develop a new small-scale test methodology which proved useful for quantifying the elevated-temperature performance of adhesives used in fingerjoined lumber.
The work in promoting a small-scale test methodology to replace the full-scale fire resistance test.