Is the permeance of Foamular 1/4" fanfold insulation really only .75 perms?
As found in the product properties provided by Owens Corning (See chart in link below)
They give a perm rating of .75. Looking at the product, it appears to be perforated with a number of small holes. I'm considering using this as an air barrier material for a knee wall, but concerned with the low permeance. Is the permeance rated on a per inch basis?
Owens corning provides data showing permeance of .75 for 1/4" and 3/8" fanfold, and 1.1 for half inch, 1 inch, and 2" foamular. I thought it varied based upon the thickness of the product?
Posted Jun 26, 2014 3:57 PM ET
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