Zed-Purlins are fixed to the rafters, sides, and gable-ends of a building, providing essential support for roof and wall sheets. They come in varying lengths, depths, and gauges, tailored to the specific size and requirements of the building.

The specification of the Zed-Purlin required depends on factors such as the size of each bay, the end-to-end span of the building, and the load factors. These elements determine the appropriate Zed-Purlin configuration to ensure optimal strength and support for the structure.