Great show! The carpet in my family room is a few years old now and it needs replacement. The problem here is that this carpet was installed directly over the concrete floor in the family room, and I would like to change that. I am planning to remove the carpet, install some half-inch plywood and then install the new carpet over the plywood. My question is, what is the best vapor barrier or other material to install under the plywood considering our cold climate here in Ontario, Canada?