metal building insulation and condensation?
I just closed in my new building with a metal roof and wood siding. The roof is 2×6 (errors) between a wood lattice frame type. I am concerned about condensation on the underside of the metal. I'm going to insulate the roof with r-19 fiberglass face up to the metal and the walls with fiberglass R-11 side. I bands close to the apex and lateral wall where the metal meets so it is all sealed. Having the building insulated and heated, is my insulation on the roof going to get all wet?
Oh, it will be wet ….. The only method that will ensure no condensation of poly iso foam sprayed. You can try isolating baffles as described in another response, but without a vapor barrier PERFECT / retarder, moisture is still using the metal surface. Here's a link to a site for the product I spoken. I saw it installed, the trick is awesome.This stuff is gets into every nook and cranny. If you choose to use it, ask someone with experience in construction for use with metal roof. http://www.eere.energy.gov/consumer/your_home/insulation_airsealing/index.cfm/mytopic=11590
Metal roof ridge cap