A lot of people decide to carpet their homes not only because it makes their home warmer in the sense of being inviting, but also because carpeting also makes and keeps a room physically warmer than, say, tile or hardwood. In fact, carpeting can insulate a room up to 10 times more than hardwood floors [source: Carpet Institute].

R-value is the thermal resistance rating of a carpet. The R-value is based less on what the carpet is made of than on the actual thickness of the carpet. Often you can find the R-value on the label when you are shopping for a new carpet, but if it's not on the label you can figure out the carpet's approximate R-value on your own. Just multiply the carpet's thickness in inches (including the carpet pad) by 2.6 [source: CRI].

It's important to consider how well a carpet will insulate your home and not just how it will look. One study found that the carpeting in elementary schools saved an average of $2,000 to $8,000 on heating. According to the Carpet Buyer's Handbook, after nine years of saving money on energy bills, due to having carpeting, you will end up recouping the cost of your carpet [source: Cooper].

Another thing to keep in mind when buying a carpet is its color. Of course, you're going to choose your carpet's color based on your personal taste and the color scheme of your home. But you might not know that your carpet's color will also have an impact on the warmth of your home. Dark-colored carpeting absorbs and radiates more heat than lighter colors. So if you're trying to decide between a cream-colored carpet and a brown one, consider the amount of money the brown one will save you over the years as it contributes to the heating and insulation of your home.