The type of material that is adhered to the back of a rug is referred to as rug backing. The material that is chosen to back a rug is important for a number of reasons. Rugs need to breathe in order to help air, gas, and moisture move through the rug. Without the proper type of rug backing, a rug may succumb to mildew, mold, extreme wear, and some types of rug backing may even ruin floors.

Most machine-made rugs include heat-set backings. These backings are applied to a rug through a high heat process. Heat-set backings allow a rug to breathe properly, which makes this type of rug backing an optimal choice. Many machine-made wool rugs often have heat-set backings. Contrastingly, animal hides are not always an optimal rug backing choice.

While some expensive animal hide rugs may have been well-prepared, most of them are not. This means that an animal hide doesn't breathe particularly well, and some hides may even require additional backings in order to prevent the hide from curling. For this reason, cheaper animal hides do not last very long, though they are a natural choice.

Olefin rugs can be inexpensive rug options, but they generally come with woven backings that can actually damage floors. To find out if a rug has a woven rug backing, simply turn the rug over. If the back of the rug is not covered with any other kind of material, it is probably a woven rug.

Bathroom rugs and throw rugs that are covered completely by latex are often the worst kinds of rugs that can be purchased. These rugs do not breathe at all, and they can damage all kinds of flooring. Laminate flooring will often turn a yellow color when a latex-backed rug is used. Hardwood floors will warp and sink over time thanks to latex, and even concrete floors can show signs of visible damage caused by latex. Latex actually attracts moisture, which will seep into the floor underneath the rug.

Before shopping for any kind of rug, make sure to pay attention to the type of rug backing that is attached to a rug. While most consumers only research types of rugs, the back of a rug is extremely important. As a general rule of thumb, rugs that are more expensive tend to have better quality backings, though this isn't always the case. If the material used to cover the back of a rug cannot be easily determined, speak with the manufacturer of a rug. When it comes to rug backings, it is far better to inquire about a rug than to ruin a floor with the wrong kind of backing.