One layer of insulbright isn't enough to insulate you from the heat. I use at least 3 layers of something in a pot holder to keep from getting burned. The additional layers can be cotton batting, old mattress pads, old towels, ... I wouldn't use polyester batting. It could be melted with the heat in an oven. I'm not even convinced that insulbright is needed. It was a solution to a perceived problem. I do have some, though and have used it.