My living area ceiling is insulated with bat insulation with the paper vapor barrier under the fiberglass (paper on heated / living side). I want to add a new finished room in the attic and floor over the existing bat insulation. The room will be insulated with the paper barrier in. However, should I be concerned about any moisture problems with a "double" paper vaper barrier. One paper vapor barrier under the attic floor (original construction) and one barrier added with the new room (new walls and ceiling)? Or should I remove the original ceiling (attic floor) insulation first prior to construction?