My house has an attic that is well insulated with a layer of insulation between the joists and an extra layer of insulation on top of that going that is run in the opposite direction. I have found myself to run out of storage space in my house and am thinking of turning my attic into useful storage space. I do not want to do this wrong and loose my R value. So this is where I am kind of stuck as I do not want to just place plywood on top off the extra battings, and if I remove the extra battings I will lose my R value. I have seen part of an episode when the guys where re-insulating an attic and at the end it was briefly mentioned that if someone wants to have the storage but R value, use Styrofoam insulation then plywood on top. If you can help me out with direction on how to perform this modification it would be greatly appreciated.