What is included in the Stramit® purlin guide?

The Guide contains details on all Stramit® Purlins, Girts, Bridging and relevant accessories. Information is provided to enable detailed purlin design including a wide range of practical component assemblies to cover almost all applications. Stramit offers a wide range of standard C and Z purlins from 100 to 350 deep in several thicknesses.

Do I need a bridging inspection before installing a purlin?

It is imperative that this be resolved immediately and prior to installation. Purlins and Girts supplied by Stramit will be made from high tensile galvanised steel. Final inspection of the installed purlin, girt and bridging system should check for correct bolting of laps and that bridging is correctly in place.

What is the bolt strength of a roof purlin?

The bolt strength grade (4.6 or 8.8) should be specified by the design engineer to conform with the Stramit® Purlins, Girts & Bridging – Product Technical Manual. Loads to be suspended from roof purlins must be accounted for in design. No allowance is included in the capacity tables.

What bolts do I need for a purlin?

Normally M12 bolts are required for purlins between 100 and 250, whilst M16 bolts are needed for 300 and 350 purlins. Each bolt requires integral washers. The bolt strength grade (4.6 or 8.8) should be specified by the design engineer to conform with the Stramit® Purlins, Girts & Bridging – Product Technical Manual.

Why do large purlins require large bridging systems?

Large purlins require large bridging systems due to the larger spans and heavier loads encountered. These bridging components are conventional in nature but on a much larger scale. Generally the bridging channel is a C150 section firmly bolted to end plates to suit the particular purlin concerned.

How should a purlin flange be connected?

Any such loadings must be connected to the purlin web by using hangers or other means. Never attach loads to the purlin lips. Attachments to the purlin flange must be within 25mm of the web. Connection design should follow the rules within AS/NZS4600, including a check on bearing of the purlin. Loads should not be suspended from wall girts.