I am making a cottage over into a full year round home. The porch is becoming part of the house. I need to insulate the ceiling. There isn't much room and I had heard of an insulatin that is coned, to allow air flow. Has anyone else heard of this and if so where can i get it. Also, if not, any suggestions about how to keep from losing a lot of ceiling height while still getting enough insulation into the ceiling. It is a cold climate of upstate NY, lots of snow.