I would never install a metal roof on this without decking and underlayment, no matter what some manufacturers or contractors may say. With this type of construction, there us far to great of a risk of condensation. You need a vapor barrier behind your walls / ceilings, insulation, vented air space, decking, underlayment, and metal roof to do this right ... and also to avoid ice dams.
Todd Miller
2015-11-22 19:41:15.000000
We are building a new A frame cabin with a 12x12 pitch roof. The 2X10 rafters are 24" on center. I would like to put a metal roof on the cabin, and have a couple of questions?
1. Do I need to sheet the roof? I am lazy and would like to simply strap the rafters with 2X4s and apply the metal roof to the strapping.
1. Do I need the felt under the metal OR under the strapping? My thought is that it will simply restrict the air flow if the roof is not sheeted.
Bob Bryenton
2015-11-22 19:34:34.000000
+1
If you are going to heat the cabin, that roof will sweat like you are in a steam room depending on the climate.
Between both the ability to insulated and long term durability, I think a solid deck is the way to go.
