Donald writes from Richardson, Texas: "My attic floor is rated R-30 using Owens Corning (OC) pink loosefill fiberglass. I am trying to upgrade it to R38 or above. But no companies (Home Depot and other vendors in your web for this area) sell OC loosefill fiberglass. They do carry OC rolls and Batts. Do I get some OC Kraft R13 rolls and put them on top of OC loose fill? Or do I have to scoop up loose fill and use OC R13 kraft batts on the bottom? If neither is good choice, can I get some R-13 Kraft batts stapled between the roof rafters?"

Answer: Retail stores typically do not stock loosefill insulation because it must be installed with special equipment that fluffs it up to achieve the proper R-value. In your situation you can just lay batt insulation over the existing blown-in insulation. There will be some minimal loss in R-value due to compression of the blown in insulation by either the weight of the new insulation or foot traffic while installing it.