can it be removed from the encapsulation and used without it?
no vapor barrier is needed and if one is present it will trap moisture, will be adding the fiberglass insulation to an attic that now has 3 1/2" fiberglass backed on one side with paper
encapsulated fibergalss insulation
Dec 13, 2004
4 Replies
check the packaging. I have recently purchased some of the Johns Manville encapsulated insulation and it specifically says "does not provide a vapor barrier". If you look at the stuff, it's perforated both sides. The stuff you're using may or may not be the same.
it is comfort therm encapsulated fiberglass insulation by johns manville, in the product description on their site at
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it says "The plastic facer also serves as a vapor retarder." whether a vapor retarder is not a vapor barrier i don't know
on the wrapper the insulation comes in it says the facing is flammable and should only be used in applications where gypsum board is put over the top of it
If it is the stuff designed to make it easier to handle it has small holes in the plastic and that will allow the area to breath. It does not act as a vapor barrier, it only will slow it down a little.
seems another reason to remove it from the encapsulation for an attic retrofit is the facing is flammable, on the product wrapper it says "Kraft facing is FLAMMABLE and should not be left exposed.", no reason to have exposed flammable material in the attic
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