How to Insulate a Floor on a Concrete Slab
LESLIE: Donna in Texas, you’ve got The Money Pit. How can we help you today?
DONNA: We had the most unseasonable cold in record history in our part of the world this year and we’re looking at doing wood flooring downstairs. We’ve completed the upstairs.
DONNA: And on the upstairs, where we had subflooring, we put cork between it and the preattached foam that went on back of the boards.
DONNA: On a slab – and I know there’s varying things but on a slab is – what can we do, aside from that flimsy, little piece of foam that’s glued to the back of those boards? What else can we do that can insulate against cold on the slab?
TOM: Well, you can first put down a vapor barrier and then you – there’s special types of underlayment that’s designed for – what kind of flooring are you putting down? Laminate floor?
DONNA: We did laminate upstairs because there’s not that much traffic.
TOM: Right. But what do you want to put downstairs?
DONNA: But we were thinking about doing real wood downstairs.
TOM: You want to put real wood on top of concrete?
DONNA: Yes, sir.
TOM: Yeah, you can’t do that. You have to use engineered hardwood. You can’t use solid hardwood on top of concrete, because it’s too damp and it’ll buckle. So, underneath the engineered hardwood, you’re going to use an underlayment there. And that sort of comes in a roll and it’s like a thin insulation and that’ll help a little bit. But if it’s that uncomfortable, because of the temperature, then I think you’re going to have to supplement this with some area rugs.