Question:
How much stiffness does a metal roof alone add to a surface? In the case of 2x4 purlins atop common rafters, will the metal roofing adequately prevent racking? Or, should some additional wind bracing be used?
I ask the question because I'm putting on a roof similar to what Brad describes. The utilitarian buildings that I've looked at with metal roofing on 2x purlins don't seem to have wind bracing, so I've assumed that the attached metal skin will stiffen it up on its own. Is this a correct assumption?
