I've got a 30 yr old 4 bedroom ranch. My furnace is in the garage. There are only large two air returns in the house. One is on the other side of the wall from the furnace in the living room, and one is on a far hallway away from the furnace. When the bedroom doors are closed and the furnace is on I can feel a definite outward draft under and around the doors. Would there be any problem with putting a 6-8 inch return from the bedrooms into the hallway to relieve the pressure? Would I be better off to plumb it into the existing return pipe? Would this help at all? Any suggestions would be appreciated.