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TOPIC: Installation Process

metal roof install

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Hi, We had a new metal roof installed on our addition. They layed strapping across the roof rafters then layed down the metal roof. I asked them why they did not put down an underlayment with felt paper then the metal? They said it was ok to install it this way. Problem is, in the winter there is alot of moisture/condensation in the attic on the underside of the meatl roof. Just rercently I was speaking to a neighbor and he said it was installed wrong. He also said he believes there is some sort of insulation that can be sprayed on the underside of the metal roof to stop this problem If this is so what is the product. If not how do I fix this without removing the roof. This is the unfinished attic area and the moisture /condensation will drip into the attic insulation, inviting mold/mildew. Thanks for any info. Tom
tom curtis

7/28/2006
Many metal roofs can be installed that way but a key to making it work, especially on a residential job, is to have very good attic ventilation and also, preferably, a vapor barrier behind the ceilings and lots of insulation in the floor of the attic. I would take a hard look at how any of these might be improved in your situation, especially the ventilation. Contact the manufacturer of your roofing for assistance. Todd Miller
Todd Miller
Isaiah Industries, Inc.

7/30/2006
Hi and thanks, but is there some sort of material that can be sprayed ontpo the underside. If not is there any thing to put up against it(foam etc) and then cover that over with plywood?
tom curtis

8/16/2006
You could spray isocyanurate foam to the bottom of the roofing. Decking would not really be necessary -- again, provided your metal panels are okay for installation in this manner. Todd Miller
Todd Miller
Isaiah Industries, Inc.

8/16/2006