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-   -   Two layers of faced drywall in attic - remove one or both? (

TomServo 04-19-2010 02:47 PM

Two layers of faced insulation in attic - remove one or both?
EDIT: I mean insulation, not drywall, obviously...I'm an idiot on Mondays... :eek:

I have (you guessed it) two layers of kraft-faced fiberglass insulation in my attic. I understand this is bad (two vapor barriers), but I'm not sure exactly how best to deal with it. I'm thinking I want to add blown-in cellulose, anyway, since it performs better than fiberglass in cold weather (I'm in Minnesota).

Should I remove both layers of fiberglass and then add the cellulose? Or would that just waste perfectly good insulation? The bottom layer is, unfortunately, the worse of the two. It seems to have all but disintegrated over the years. I don't see mold, that I can tell, but I know that doesn't mean it isn't there.

In terms of insulation performance, since cellulose does better than fiberglass at lower temperatures, wouldn't it be better to go entirely with cellulose? Or at least not have fiberglass as the bottom layer?

Earnie 04-21-2010 07:49 AM

Tom, you must have had the same insulation contractor as I did and I live in NC.

I too have two sets of faced fiberglass insulation in my attic. Both R19. I also have not seem any evidence of mold.

I have talked to a few insulation contractors. Interesting that a few don't think it's a problem. Maybe they just didn't want to deal with me and my insulation issue.

I have yet to decide what to do but will probably remove one layer, add it to the growing landfill, them have blown-in fiberglass insulation added to bring the attic up to current R value.
