Quick question, I am building a shop over a connex and have 8” purlins at 9’ center lines. My question is can I lay 4” purlins flat to screw in my r panel keep in mind it’s all metal construction.
I don’t quite follow your question but here’s how my building is constructed. The roof and side panels are screwed directly to the on edge purlins. Professionally erected following the manufacturer’s design.