Handling and Installation


handling



During unloading and erection, trusses should be handled with care. Proper lifting equipment is to be used at all times. They should be transported in the vertical position to minimize the strain on the plated joints.





Wood trusses can be installed by hand if their size and configuration are such that they can be handled into place without causing an excessive lateral deflection of the truss. Any lateral deflection greater than 75mm (3") is considered excessive.





Trusses installed by mechanical means should be supported at intervals of 7.5m (25') or less. Adequate rigging (crane, fork lift, slings, tag lines, spreader bars, etc.) should be used to ensure safety and prevent damage.





Lifting devices (slings, chains, cables, nylon strapping, etc.) should be connected to the truss top chord with a closed-loop attachment. Trusses will be placed according to framing plans. They will be held with the hoisting equipment until the ends of the trusses are securely fastened and temporary braced.





The maximum angle between lift lines (Ý) should not exceed 60 degrees in order to minimize lateral distortions in the truss.

A truss layout drawing showing the location of each truss type on a roof or floor plan, and a shop drawing for each truss should be included with each truss shipment. The layout should also include all hardware required for Truss connections and tie downs. The hardware list must indicate type, manufacturer & capacity as well as specific nails or fasteners required.


Figure 2: Truss General Arrangement Drawings