Metal roof underlaymnet
user-7076651
| Posted in General Questions on
Hi,
We are installing standing seam metal panels on a porch roof and would like advice on the underlayment. The roof is a simple shed with a 2 1/2 : 12 pitch. It will be unvented with 1/2 plywood decking on the rafters and 3/4” t&g boards under the rafters. We have asphalt felt and synthetic felt onsite but should we use peel and stick made for metal roofing?
Thank you!
J. Greene
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Replies
J., if you are in a cold climate, your building code probably requires ice and water shield in 24" horizontally projected from the outside face of your wall. A single 36" strip is often enough. Ice dams may not occur over a porch, and if they do the damage won't be as severe as it would be if over living space, but there's not really a downside to using it. Just make sure it's rated for use under metal roofing--it's no fun to see asphalt dripping down your fascia, trust me.