I live in Northern Ontario and have begun to insulate the perimeter walls of my basement. The walls are concrete block. Initially I installed tar paper against the concrete and then built walls form 2X4's and installed them 2 inches from the concrete walls. I then insulated with R24 batt insulation. I noticed today that where I have insulated that there is frost between the tar paper and insulation on the wall above ground level. Is this because I have not yet installed a poly vapor barrier? Any other suggestions? I am some what frustrated at the moment!!!!!!!!!!!!!!!