Can I put unfaced insulation on top?
Mark writes from West Springfield, Massachusetts: “I read your blogs regarding insulating over existing. I want to do this as well. The current floor insulation in my attic is quite strange. There is paper on both sides and the insulation is in the middle. Can I put unfaced insulation on top of this or should I remove and put in R-25, faced down toward living space below. I would like to just add unfaced R 19, but not sure with this old (but dry) 2″ insulation.” Answer: I would leave the old insulation in place and let it continue to work for you. Since the existing insulation seems to already have a vapor retarder, add unfaced insulation. Regarding the fact that the existing insulation has paper on both sides, you generally don’t want a second vapor retarder but there can be an exception when the insulation you are adding is twice the R-value or more than the insulation already in place. That is clearly the case here. Another option is to freely slash the top paper on the existing ins
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