Exposed fastener metal roof vs. standing seam?
I’m reading Martin’s awesome roofing primer: https://www.greenbuildingadvisor.com/blogs/dept/musings/martin-s-ten-rules-roof-design
And I came across something a little confusing to me: the preference of an exposed-fastener metal roofing over standing seam. I think I understand that an exposed fastener job is easier to install and therefore cheaper. But is that it?
I keep hearing that the disadvantage is that the screws will eventually back out and the holes in the panels will enlarge and it’ll leak. Is this actually true? I also see in the comments that some people screw exposed fastener roofs into 1x strapping that goes over the roofing felt. Is this to minimize the consequences of these potential problems?
So what’s the deal? Is an exposed fastener roof installed on 1x strapping going to last? Ignoring aesthetics, is there any reason to prefer a standing seam roof?
I ask because there’s a lot of local expertise for exposed fastener roofs vs standing seam, and I’d prefer to go with the flow when I redo the roof on my house.
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