Hot-rolled steel purlins predate modern metal building systems by decades. A multitude of industrial buildings constructed since the beginning of the twentieth century utilized hot-rolled channel and ...

acts as part purlin and part girt its top flange supports roof panels, its web, wall siding (Fig. 5.1). FIGURE 5.1: Typical eave strut. Girts, purlins, and eave struts exhibit similar structural ...

And that's a bargain when you consider the benefits. A metal roof typically lasts 30 to 50 years and instead of covering the whole roof with plywood, you just nail a few 2x4 “purlins” across the ...