Rich writes from Meriden, Connecticut: "I have a large amount of left-over R-19 faced insulation. I'd like to use it as a second layer over my existing attic insulation. I know I should be using UN-faced insulation but wonder if I can either pull off the facing, or just make a lot of "slits" in the facing to disable the second vapor barrier?"

Answer: Disabling the vapor retarder by slitting it is acceptable. Install the product with the facing side down after the vapor retarder has been disabled.