basement insulation - followup
#1

Contractor suggested applying poly barrier between drywall and insul. AND between the insul and concrete wall up to grade level (have approx. 2.5 feet above grade). Will this create a double barrier that could rot the studs or will leaving the top open between the insul and concrete prevent this? Bottom line, should I apply the second layer of poly against the concrete or forget it?
#2
You've asked an age old question that seems to have no clear answer. If your foundation wall isn't wet, then I'd skip the barrier against it. If your foundation wall is wet, then I'd fix that first.
#3
I've asked this same question on this and other forums, and to several contractors and home improvement centers. I've gotten just about as many different suggestions. What I decided on was this. My concrete walls are not wet or even damp, but I was concerned with both the double vapor barrier, and the thought of insulation right on the concrete. So I put up my 2x4 wall, leaving 1" between the wall and the concrete for air to circulate, and to avoid any moisture from wicking onto the insulation. I used standard 3 1/2" basement insulation, and I decide to run a dehumidifier also. I'm still working on the project, will probably finish this fall. I'll let you know in 15-20 years if I made the right decision...