I am in the process of finishing my basement, my plan up until a few weeks ago was to lay 1″ rigid Styrofoam directly to the concrete floor covered by 3/4″ tongue and groove plywood subfloor. Visiting a friend while he was renovating a home for his kids, he mentioned that he was using reflective insulation in many areas of his project. As I started to research this product I was surprised by the number of companies and number of products that are available.
I have emailed 4 companies and actually talked on the phone with one of them. They have all convinced me to change my original design by replacing the rigid Styrofoam with a layer of reflective material directly to the concrete, installing 3/4″ furring strips then the subfloor. Although I live in upstate NY, I am not worried about an R-Value since my basement walls are spray foamed, but I do want a vapor barrier and hopefully will block any radon I have in the ground. How do I pick the best product from all this info overload? One company suggested a reflective material, the others have suggested bubble material, which they are suggesting the double bubble over single bubble. I asked one company why I need double bubble over single since one surface will be in direct contact with the concrete floor and he said it wasn’t that much more in price and it was easier to work with?
I would like to use one of these products due to easier installation and cheaper in the long run.
Please help me make sense of all the info I have gotten so far, and dispel some of the myths and marketing I am receiving from these companies!
Answer
You may use either the single bubble or double bubble reflective insulation, and you could use one with a single sided reflective surface as long as it faces the underside of your sub-floor. Since the down side will be in direct contact with the old floor, it will not be able to reflect heat. The difference between the thermal value of the single bubble and double bubble is probably not measurable as the real work comes from the reflective surface. You can go to the verification products page and pick any other the companies that have the product you want from there. That way you’ll be sure to get a good product. Performance wise they are all the same.