"It's easier to put on slippers than to carpet the whole world."
Carpet cushion (carpet padding) is the foundation for every residential carpet installation. Despite what you may be told, carpet padding plays an important part in the performance of your new carpet installation. However, the old adage that if you must choose between less expensive carpet and less expensive carpet padding, choose less expensive carpet is not true. Carpet selection and carpet cushion selection must enhance one another. Selecting either a poor quality carpet or poor quality carpet cushion ensures a carpet installation that is destined to disappoint.
Many retailers buy carpet cushion (carpet padding) in truckload quantities, so they typically use one type of carpet padding or another. They rarely offer several options, because of quantity discounts. Do not allow this to influence your carpet cushion selection decision. If a particular retailer does not offer a particular carpet padding that your prefer, ask if it can be ordered. If the retailer cannot or will not allow substitutions, find a retailer who will.
Many consumers believe carpet cushion is used for the purpose of comfort under foot. While this a result of the use of carpet padding, the primary reason for carpet cushion is to absorb impact that the carpet would otherwise be subjected. This impact can cause synthetic latex to break down, backings to stretch, separation of the primary backing from the secondary backing (delamination) and unnecessary stress on the face fiber. The best performing carpet cushion actually provides less comfort under foot, but extends the life of the carpet installation by absorbing the abuse.
Two of the most common mistakes by consumers is to purchase a carpet padding that is too soft or too thick. Carpet cushion that is too soft, bottoms out when exposed to foot traffic. This allows the carpet to assume the rest of the impact burden; thus shortening carpet performance life.
What can get confusing is the various methods of rating carpet cushion performance. Some carpet padding is rated in density, but there are various methods for determining density. Terms like indentation load deflection (ILD), indentation force deflection (IFD), compression load deflection (CLD), compression force deflection (CFD) all may be used to describe the test method for evaluating carpet cushion density. Essentially these terms are a method of evaluating how much weight is required to bottom the carpet cushion out. Some of these methods use a square inch as the area for evaluation, while others use a broader are such as 6 or 8 square inches. It is important to note which method is used when comparing carpet padding, because an 8 lb. carpet padding using the broader area of evaluation may equate to a ½ pound rating for a square inch measure.
Also, carpet cushion may be rated in weight per cubic yard. An 8-pound carpet cushion may weigh 8 pounds in a standard 3 ft by 3 ft by 3-ft cube. A flat rubber carpet padding may weigh 22 pounds per cubic foot and a prime urethane carpet cushion may weigh only 4 pounds, but the ultimate performance factor is how many pounds per footfall area will it take for the carpet cushion to bottom out.
The second most common mistake is to purchase carpet padding that is too thick. You may be told that a thicker carpet cushion will cause performance problems, but the primary reason for selecting thinner carpet padding is so the carpet is not so high from the floor that it will not hold on to the tack strip. The carpet industry has established a maximum recommended thickness of 7/16 inch, but you should never exceed ½ inch. The thought process here is if ½ inch is recommended, retailers will go to 5/8 inch. A ½ carpet cushion provides adequate cushion and still allows the carpet to hold on to the tack strip along the walls.
Waffle Rubber: Waffle rubber, like the name implies falls within the ½ inch recommendation but because of its waffle texture, this measurement include air. This is a good carpet cushion, but in the past, its filler percentage was very high and the carpet padding tended to break down over the years. When carpet was replaced this carpet cushion reverted back to its original state of Georgia clay. Today’s waffle carpet padding performs much better than the waffles of the 1970’s and 80’s. Shop before deciding on waffle rubber. Get the heaviest carpet cushion you can find.
Urethane Foam: Urethane foam is available in different densities and thicknesses. Densities of these carpet cushions can be as low as ½ pound per square inch (psi). Some of these densified prime urethane carpet padding can be very good performers, but make sure you know what you are buying. Don’t allow anyone to discourage you from purchasing this carpet cushion, if the density is appropriate.
Bonded Urethane: This carpet cushion is also called rebond and is the most popular type of carpet padding sold today. It is made from reclaimed scrap of high-density urethane foam used in furniture and automotive manufacturing, which is bonded together to form carpet cushion. Rebond comes in various thickness and densities. The density is rated as a function of weight in pounds per cubic foot. For example, a 5-lb. rebond cushion would weigh 5lb per cubic foot. The Carpet Cushion Council recommends a cushion of at least 5lbs and 3/8-inch thickness for light traffic areas, and 6.5 lbs. and 3/8 inch for heavy traffic areas. These are minimum guidelines and keep in mind the CCC is the trade voice for the carpet cushion (carpet padding) industry. Many carpet manufacturers recommend a minimum of 8 pounds per cubic foot.
One concern that you should be aware of with rebond carpet cushion is a chemical compound known as butylated hydroxy toluene (Bht). Bht is a common additive in foods, breads and cereals and is an antioxidant and has no known health effects. It is added to some urethane products to reduce the risk of fire during manufacturing. Unfortunately, this chemical compound has then tendency to produce yellowing in many carpet constructions. If you have purchased a rebond carpet cushion and yellowing has occurred, rinse with white vinegar or other mild acid before applying a detergent solution. Detergent solutions have the tendency to permanently set the yellowing. It is best to ask for written assurances from the retailer that the carpet padding that you choose does not contain Bht.
Flat Rubber: For the ultimate in luxury and long wear consider using 19 -22lb density flat rubber carpet cushion. This is the carpet padding that I prefer for my own home, but it is extremely pricey and difficult to find. The average consumer would not consider this carpet cushion because of its cost. However, my 10-year-old olefin Berber looks it was installed last week. While it is recommended that you replace carpet cushion with each carpet installation, flat rubber may be the only carpet padding that could outlast the carpet and survive a second carpet installation.
Fiber Cushion: This carpet padding is used primarily to take advantage of scrap fiber and promote environmental stewardships. Frankly, I have been disappointed with the performance of these carpet cushions. Other fiber cushions made from jute, or hair mixed with jute, perform better but I would recommend the cushion products listed above.
Every carpet installation should begin with the best quality carpet padding (carpet cushion) that you can afford. Carpet pad selection is essential to carpet performance. Carpet padding (carpet Cushion) density and carpet padding thickness each contribute to carpet performance.