Another drywalling question for you. I just bought a house & the garage is insulated w/vapor barrier but no drywall on the walls. It looks like the previous owner used 6" insulation rather than 4" insulation between the 2x4 beams as the plastic billows out between the 2x4's. I am going to use 1/2" drywall to cover these walls. Will the drywall bow out between the beams over time because of the extra thick insulation?