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 ...

Roof secondary members, known as purlins, often form an essential part of horizontal ... Since most secondary members normally encountered in metal building systems are made of cold-formed steel, our ...

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 ...