Never attach roof sheathing with staples.
No sheathing under roof.
When open cell spray foam is used a low perm class ii vapor retarder is installed where required.
8d ring shank nails should be used instead.
How to prevent condensation under a metal roof.
While metal roofing doesn t require plywood underlayment there are circumstances in which you may wish to install plywood to anticipate future roofing needs or to offer additional soundproofing.
The current state and local building codes for the minimum r value of air impermeable insulation required for the roof assemblies in the home s climate.
Sheathing is installed perpendicular to roof trusses.
3 benefits of rigid foam sheathing.
Underneath it is the attic space followed by a suspended ceiling.
Currently there is no sheathing or tar paper under the metal.
It is nailed directly to the rafters.
Plywood has an r value of 1 25 and fiberglass batts have an r value of 3 14.
A leak free roof membrane that is fully adhered to the roof sheathing should be installed.
More effective insulation with r values ranging from 3 6 to 8 0 rigid foam sheathing has much better insulation per inch than other materials i e.
Roof sheathing comes in grid marked 4 by 8 foot sheets and should be installed perpendicular to the frame.
If you re wondering how to prevent condensation under a metal roof you re not alone.
July 28 2017.
Owners of agricultural buildings man caves and horse barns all are worried about the corrosive effects of condensation.