Roof Truss Lateral Bracing

To strengthen the roof system truss clustering cross bracing and wind bracing is recommended at both end of the buildings and every 20 for longer span buildings.

Roof truss lateral bracing.

7 2 9 bracing for trussed rafter roofs trussed rafters shall be suitably braced to support applied loads and self weight without undue movement. Continuous lateral bracing or restraint is very important. Hold these restraints in place with two nails each. Permanent bracing listed on the truss design drawing for specific web members and permanent bracing for the roof or floor system.

Diagonal braces are required at each end of a truss row and repeated every 10 truss spaces 20 maximum. Individual truss member lateral restraint and diagonal bracing the truss designer identifies the location of required individual truss member i e web top chord or bottom chord restraint bracing. Roof sheathing plywood osb provides effective lateral bracing when sheathing is nailed directly to top chords. There are two separate types of bracing to be concerned about.

When truss spacing exceeds 2 feet purlins are generally required to support roof sheathing. If trusses are not designed with stabilizer see bcsi 1 for stabilizer spacing and diagonal cross bracing required. For the purposes of this chapter the guidance and use of standard trussed rafter bracing does not apply to homes on or near exposed sites e g. Purlins 24 oc are typical along with the bottom bracing shown.

This condition generally applies when trusses are spaced at 2 feet. Type of load important. Diagonal bracing installed for the purpose of increasing the stability of the truss system during installation shall be installed on web members verticals whenever possible located at or near each row of bottom chord lateral restraints. Certain truss members require bracing in order to carry the full design load.

The stabilizer must be supplemented with diagonal bracing in the roof and ceiling planes and cross bracing in the web plane at required intervals shown on the individual truss design drawing tdd. This bracing serves the purpose of preventing out of plane buckling due to the applied loads shown on the truss design drawing.