S307-M1980 (R2006)

1. Scope 1.1 General This Standard covers the load test procedure for evaluating the strength and deformation performance of wood roof trusses intended for use in housing and small buildings as defined in Part 9 of the National Building Code of Canada. Note: Part 9 of the National Building Code of Canada provides detailed requirements for the construction of houses and small buildings up to 600 m² in building area and 3 storeys in building height and applies to all occupancies except assembly, institutional, and high-hazard industrial. 1.2 This Standard does not stipulate mandatory performance criteria (see Appendix A for acceptable performance criteria). 1.3 Intent of Test This load test procedure is intended to evaluate the adequacy of wood roof truss designs and is not intended as a quality control test. The procedure may, however, be used for retesting production run samples in cases where the quality of the truss is in dispute. Note: It is recognized that measures to ensure the quality of production of trusses must be maintained for on-going production of designs acceptable under this Standard. 1.4 Limitations Assemblies to be tested by this procedure are limited to: (a) Triangulated trusses having a maximum span of 12 m; or (b) Bowstring or lenticular trusses having a maximum span of 4.3 m; whose members are connected using mechanical connectors or nailed gusset plates and which are intended to be installed at a maximum spacing of 600 mm on centres and in such a manner that the top chords are suitably sheathed or braced to prevent lateral buckling. Note: Clause 2 has been renumbered A2 and has been relocated in Appendix A, page 18.