text:  My basic question is I don't want to create anything that's going to... Well, you don't want to get two vapor barriers into a wall. So, you know, I mean, when you talked about foam, number one, that's the best thing to use, quite honestly, because you're going to get a higher R value per inch of thickness. So that's good. And you can have a choice of breathable or non-breathable water vapor or non-water vapor.