I have this weird old insulation in the attic of the house I bought recently, and am wondering if it's good for anything or if I should just throw it away. It seems to be semi-rigid, but not really hard. I'm planning to put down a floor in the attic and am thinking of adding 2x6s to the top sides of the existing 2x6 joists so I could put in R38 and a floor over it. These rectangular panels are not fitted together tightly so I don't think they're probably doing a lot of good, but I might be able to use them somewhere else, as I need to insulate the whole house. I'll be grateful for any insight into what this stuff is and what its R value might be.