Alpine

T T emporar emporar y Bracing y Bracing 30 All trusses must be securely braced, both during erection and after permanent installation. Individual trusses are designed only as structural components. Responsibility for proper bracing always lies with the building designer and contractor for they are familiar with local and job- site conditions and overall building design. All trusses should be installed straight, plumb and aligned at the specified spacing. Trusses should also be inspected for structural damage. There are two types of bracing. Temporary bracing is used during erection to hold the trusses until permanent bracing, sheathing and ceilings are in place. Permanent bracing makes the truss component an integral part of the roof and building structure. Temporary and permanent bracing includes diagonal bracing, cross bracing and lateral bracing. Permanent lateral bracing, as may be required by truss design to reduce the buckling length of individual truss members, is part of the truss design and is the only bracing specified on the design drawing. This bracing must be sufficiently anchored or restrained by diagonal bracing to prevent its movement. Most truss designs assume continuous top and bottom chord lateral support from sheathing and ceilings. Extra lateral and diagonal bracing is required if this is not the case. Bracing members should be 2x4 nailed with two 16d nails at each cross member unless specified otherwise on the design drawing. Lateral braces should be at least 10 feet long. Cross and diagonal braces should run on an approximate 45 degree angle. It is important to temporarily brace the first truss at the end of the building. One method calls for the top chord to be braced by ground braces that are secured by stakes driven in the ground, preferably outside and inside. The bottom chord is to be securely anchored to the end wall. Adjacent trusses are now set connecting each to continuous lateral bracing on the top chord. These are typically spaced at 6', 8' or 10 feet on centers along the length of the truss. Refer to BCSI 1-02 for diagonal spacing. This top chord bracing will be removed as the sheathing is applied after the other bracing is completed.

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