Although it’s possible to install vinyl flooring directly on concrete, it’s not a great idea. I’ve seen vinyl separate from the concrete over time, besides the fact that a basement floor constructed this way won’t feel very warm underfoot. That’s why installing some kind of a subfloor directly against the concrete first is the best idea. There are many subfloor products on the market these days, and all work quite well. The newest type I’ve seen also happens to be the warmest. Barricade Plus (866-544-6879) is a 1-inch thick, 2-foot x 2-foot high-density foam subfloor tile that delivers R5 worth of insulation. It’s much stronger than typical types of insulating foams, and is strong enough to walk on directly without damage. According to independent testing, Barricade Plus raises floor temperatures approximately 7°C. A layer of 3/8 inch thick plywood applied over top of this foam creates an ideal surface for installing vinyl flooring.