I am finishing my basement in my new house (it is 3 years old). I using 2x4 studs, keeping it away 5 1/2'' from the concrete wall and using Rouxle insulation R-21.5. In between the dry wall and the insulation, I am putting 6mm polytrap plastic vapour barrier. Do think that it is adviseable to use typar paper (synthitic vapour barrier) between the other side of insulation and the concrete wall? I have heard of some people using felt paper (black paper) at the same place. What do you think is most adviseable? I also wanted to ask if I should keep the insulation away from the bottom stud (from the floor) for air breathing. If so, how much away?