Bruce writes from Port Arkansas, Texas: "I have added a room in my attic and have been told by A/C guy I need r30 with tar paper covering on the attic side. I would like to have your recommendations. I live in very hot and humid area."

Answer: For a finished attic we do recommend installing Kraft-faced R-30 insulation under the roof deck. The Kraft paper has a layer of asphalt that acts as a vapor retarder and the roof deck needs to breathe. The R-30 should be installed in rafters in a way that leaves one inch (1") of airspace between the roof deck and the insulation.