The rubber backing on area rugs can disintegrate over time, leaving a nasty residue on the floors beneath. Vinyl flooring, in particular, is susceptible to yellowing when exposed to rubber rug backings. You can avoid this issue by purchasing backless rugs and holding them in place with materials other than rubber, including grip tape and memory foam. You can purchase these alternatives at your local home improvement or hardware store.
Rug Grip Tape
Sold in easy-to-use rolls, rug grip tape is available in two forms. The first has adhesive on one side and is semi-tacky on the other. The second option has adhesive on both sides, like double-sided tape. You can attach the tape to the perimeter of the rug or, for larger rugs, in several strips across the rug's surface area. The tape adhesive is formulated to stop horizontal rug movement while easily and cleanly releasing from the floor when vertical pressure is applied.
Visco-elastic pads, commonly referred to as memory foam, are comfortable to stand on and come in a variety of thicknesses and sizes. These rug pads use friction rather than adhesive to keep rugs in place. They tend to be thick, though, and may not work well in areas where doors need to open over the top of the rugs. They are excellent, however, when placed in front of kitchen sinks and other work areas. The provide the softest backing option and are usually treated with mold and mildew inhibitors, as well as liquid barriers to protect your floor from spills. Memory foam pads were once frowned upon for off-gassing a chemical smell when they were new. Fortunately, more natural manufacturing processes and materials have greatly reduced this problem, so you can have the comfort without the odor.
Felt Rug Pad
Made from a mix of natural and synthetic fibers, felt pads provide a great deal of comfort and softness under a rug. Although felt pads don't possess any inherent non-slip properties, they work well under large area rugs where their sheer size and weight will keep them from moving. This style is great for sound absorption and comfort. Felt has no inherent stain or liquid repelling properties, however, and will not stop spills from reaching the floor underneath. Denser felt lasts longer but, like memory foam, it can add unwanted height to rugs used near doors.
To save time and money, most modern carpet manufacturers often back their area rugs with synthetic rubber to keep them from slipping, It is this synthetic rubber that degrades over time and leaves marks behind on the floor. Natural rubber is harvested from a plant rather than made from petroleum and does not leave residue on floors as it ages. Like synthetic rubber backing, natural rubber grips the floor to prevent the rug from slipping and is extremely thin, making it ideal for use in front of doors. Natural rubber is a good choice if your primary concern is avoiding rubber residue on your floors. Avoid it, however, if you suffer from latex allergies.