Pay special attention to carpet on concrete floors. Carpet can absorb moisture and serve as a place for biological pollutants to grow. Use area rugs which can be taken up and washed often. In certain climates, if carpet is to be installed over a concrete floor, it may be necessary to use a vapor barrier (plastic sheeting) over the concrete and cover that with sub-flooring (insulation covered with plywood) to prevent a moisture problem.
When purchasing carpeting, you should buy the best-quality carpet you can afford, coupled with the highest quality padding. In fact, the padding that goes between the carpeting and the subflooring is as important as the choice of carpeting itself. Padding provides softness and support, cuts down on noise and insulates the floor. Often referred to as “underlay” or “cushion,” padding thickness depends on the pile of the carpet above it. Padding should be no thicker than 7/16 inch, even for a very deep pile carpet. Too much cushion can actually void a manufacturer’s warranty; so, take the time to find the padding that is right for your new carpet.