Why is it important to insulate under concrete floors in basements and heated garages?
Heat moves from hot to cold. If you insulate all areas in your home with high R-value materials but fail to insulate the underside of your concrete floors, heat will escape through the ground. Many people don’t think about it, but heat in your home does heat walls, floors, and furnishings. This is why it is sensible to insulate the underside of floors. It prevents heat loss. If you are constructing a new home or building, seriously consider insulating the underside of the concrete you are pouring.