I agree, fix the roof first. and if it is a small area, remove the shingles, rolled roofing, etc. and the felt at and around the emediate area. reapply new felt (90 lb.) then your particular type of roof material, apply some henry's (roof tar) at all stages and make sure you are good and sealed up... then open up the rock inside. gypsum will seperate between the two layers of paper as its a porus material, you may not physically see it till you take it down. mold is not your friend and wet insulation and gypsum are excellent breaders for mold...