I may be doing a Cortec install in a living room on a concrete slab. It will need plastic for a vapor barrier. This Cortec has a cork backing, but it's one of Cortec's thinner laminates. Rolls of plastic sheeting can have stiff creases and wrinkles and my concern is that the vinyl laminate won't have enough weight to make the wrinkles or creases lay down. Any ideas on flattening the wrinkles or creases? Some rolls are better than others, but I don't want noises under the floor caused my the plastic.