Roof Truss Lateral Bracing

If trusses are not designed with stabilizer see bcsi 1 for stabilizer spacing and diagonal cross bracing required.

Roof truss lateral bracing.

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. Hold these restraints in place with two nails each. When truss spacing exceeds 2 feet purlins are generally required to support roof sheathing. Continuous lateral bracing or restraint is very important.

Permanent bracing listed on the truss design drawing for specific web members and permanent bracing for the roof or floor system. This bracing serves the purpose of preventing out of plane buckling due to the applied loads shown on the truss design drawing. 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. Type of load important.

7 2 9 bracing for trussed rafter roofs trussed rafters shall be suitably braced to support applied loads and self weight without undue movement. Flat coastal fringes fens airfields and moorland. Use wooden 2x4 or prefabricated metal braces as short member temporary lateral restraints between the trusses. Set each truss after the first with its top chord temporary lateral restraint aligned with the ground bracing.

Roof sheathing plywood osb provides effective lateral bracing when sheathing is nailed directly to top chords. This condition generally applies when trusses are spaced at 2 feet. Diagonal braces are required at each end of a truss row and repeated every 10 truss spaces 20 maximum. There are two separate types of bracing to be concerned about.

Purlins 24 oc are typical along with the bottom bracing shown. 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.