I would like to add insulation to my attic. I currently have about 3 inches of 40 year old rockwool insulation between the joists. I do not think there is a vapor barrier anywhere in the attic. My plan was too leave the old rockwool (or whatever it is) alone and roll out new bats of fiberglass insulation perpendicular to the joists (covering the wood joists for maximum effect). Should I get faced or unfaced insulation?
Thanks, Jason