Here's an example where the Poster says all the walls but NOT the ceiling are protected by a vapor barrier. Yet, there's a moisure problem. Is the house real tight??? FWIW, my home's vapor barrier is what's on the 'back' of the fiberglass batts. It's not wrapped. And I don't have a moisture problem. I suspect that since my home isn't wrapped AND that I have a condensate pump, my home is relatively, moisture-free.