Originally Posted By: Greg Fretwell
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If you folks are in the south I would call blown in cellulose attic insulation a defect unless there is a vapor barrier OVER it.
The rules are different if you are in a warm moist climate and the A/C is what you are insulating for.
Think about it ...
Where is the warm moist air?
Where is the cold air?
Where is the vapor barrier?
The water condenses out in the cellulose, rots it and turns it to grey muck with an R of about 1 that compromises any fiberglass you had under it.
I have an attic full.
I would not be as concerned if the insulation was imperviable to water but the vapor barrier issue is still sound. If I could actually reinsulate my attic it would be with foil backed fiberglass but that is not likely in a 3:12 attic