Secondary Members / Cold Formed Members
Secondary Framing Systems
Secondary framing includes the structural members that support the roof and wall sheeting while transferring loads to the primary framing. These typically consist of roof purlins, wall girts, eave struts, clips, and similar components.
Roof Purlins
Roof purlins are cold-formed Z-shaped profiles, generally 200–250 mm deep and made from steel with a thickness of 1.6–3.15 mm. They are attached to the top flanges of rafters using clips, with the purlin web bolted to the clips. The ends of adjacent purlins overlap, creating a continuous beam effect to enhance structural performance.
Wall Girts
Wall girts are also cold-formed Z-sections, typically 200–250 mm deep and fabricated from 1.6–3.15 mm thick steel. They are fixed to the outer flanges of side wall columns and can be connected in two ways:
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Standard Fixing – Girts are attached to the column flange using clips, with the girt web bolted to the clips. Overlap connections are provided to achieve continuous beam action.
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Flush Fixing – Endwall girts and flush girts are aligned with the outer flange of columns. They are connected using clips bolted to both the column web and the girt web, ensuring a neat and flush finish.
