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Jim Zborowski
03-21-2008, 03:00 PM
Looked at a metal pole building this afternoon with moisture issues. The insulation contractor installed kraft faced rolls with the paper against the metal. The inside surface then had visqueen applied as a vapor barrier, with plywood walls added over it. Naturally, the fiberglass is wet from moisture and turned black, the back side of the metal panels is wet, and there is visible growth on the plywood.I am trying to find something in print stating this is incorrect. Fiberglass is white, so I'm thinking it could be Johns-Mansfield. Allegedly the installer told one of the maint. people they do this all the time ( he worked for his dad who was an insulation contractor and just knew it wasn't right ), now they are unable to contact the installer as he is out of business.
I know I've read it in here before, just can't find it.

David Banks
03-21-2008, 03:27 PM
http://www.woodmaninsulation.com/Kraft%20Faced%20MR%20Data%20Sheet.pdf

Kraft-Faced Batts and Rolls (http://www.jmhomeowner.com/products/product.asp?category=FiberGlass&Product=KraftFaced)

Jerry Peck
03-21-2008, 03:53 PM
Looked at a metal pole building this afternoon with moisture issues. The insulation contractor installed kraft faced rolls with the paper against the metal.

What you have is two vapor barriers (the metal and the plastic) so the only water getting into the insulation would be condensation due to the dew point being 'within' the insulation.

If the plastic sheeting had not been installed and the paper facing installed on the conditioned side (as it should have been), then you would have a vapor retarder (the paper facing) and a vapor barrier (the metal).

I really don't see that installing the insulation in a metal building is going to require a vapor barrier (should have used unfaced insulation) simply because the metal itself is a pretty good vapor retarder / barrier. :)