What is the proper insulation material/placement for a metal roof??

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What is the proper insulation material/placement for a metal roof??

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Please help as we have gotten so much conflicting info from vendors on this. We inherited a home with an old tin roof which we replaced with a state of the art metal roof. The orginal was attached to stringers only. Our contractor added subply and felt paper. There was never any insualtion in the "floor" or anywhere in the attic. We have been told to put traditional roll type fiberglass in the "floor" and have then been told - no, no, no - put a foil backed with kraft paper below the roof line. What is the appropriate method? In the winter we have had snow/ice slam down off the roof and hang up in the gutter. Many thanks for answering this basic question.
Guest User
2006-09-30 20:08:30.000000
I also Have an old metal roof Approx. 1915 or so. I also get Ice damming and condensation under the metal roof panels. (there is no condinous sheathing under the metal roof but 1X8's butted together down towards the eaves and about 12" OC higher up on the roof. The attic floor is currently insulated to R-19 I can't unsulate more without tearing up the attic floor because the ceiling joists are only 2X6. Can I have the underside of the metal roof insulated with Spray on Closed Cell Foam insulation?. This will act as insluation and as a vapor barrier to keep warm moist air away from the metal roof. IF this is allowed how do I detail it? do I need to let air under the metal roofing and over the insulation?
Guest User
2007-03-18 19:56:41.000000
You need insulation -- as much as possible -- in the attic floor and then good ventilation above that. Ice damming is avoided by keeping the attic cool and eliminating any hot spots in it.
Todd Miller
2006-10-02 06:19:13.000000
If you have icynene insulation sprayed and it is done properly, it will be sprayed direct to the back of the boards and roofing and no airspace is neded. Done properly, this should work. Increasing attic ventilation is another option.
Todd Miller
2007-03-18 20:08:23.000000