Step 3: Temporary bracing of top-chord plane

Step 3: Temporary bracing of top-chord plane

Truss top chords are very susceptible to lateral buckling before they are braced or sheathed. Continuous lateral bracing should be installed within 150 mm of the ridge line or centre line and at approximately 2.4 to 3 m intervals between the ridge line of sloped trusses or centre line of flat trusses and the eaves. Diagonals, set at 45° between the lateral bracing, form the required stability of the top chord. On longer span trusses, lateral bracing and diagonals may require closer spacing. If possible the continuous lateral bracing should be located on the underside of the top chord so that it does not have to be removed as sheathing is applied. This will ensure that the trusses are held securely during installation of the decking. Bracing lumber should be no less than 38 × 89 mm by 3.05 m long.