Mike writes from Oxford, Michigan: "I have approximately 12" of blown fiberglass (looks like white cotton) in my attic. It is equivalent to R30. My house was very cold and difficult to heat this past winter. I want to upgrade what is there. What should I use?"

Answer: You can have more fiberglass insulation blown into the attic or lay fiberglass batts over the existing insulation. For more information on this topic, check the Owens Corning Web site page for Adding Insulation to an Attic.