This nylon fiber is made from a mix of recycled carpet fiber and fresh feed stock. The dyes will be added later in the process. (Courtesy of Shaw Industries)

The owners of a brand-new house in 2000 were very likely to have been replacing the carpet 10 years later.

Assuming that their house was the average size for a new one that year — 2,266 square feet — and that all the worn carpeting was replaced, they removed about 146 square yards. That’s a lot of carpet, but it’s minuscule compared with the total amount taken from all the houses, businesses and institutions that replaced carpet that year.

In 2010, that total was about 833 million square yards, or as the recycled carpet industry calculates it, about 3.5 billion pounds, said Georgina Sikorski, executive director of Carpet America Recovery Effort (CARE).

If all the worn carpet removed from buildings in 2010 were placed in fully loaded, 53-foot-long, line haul trailers, and all the trailers plus cabins were placed end to end, the procession of trucks would have been about 1,238 miles long. On any given workday, based on a five-day workweek, the length of the line would have been about five miles.

Where does worn-out carpeting go? Most of it ends up in a landfill. Of the total discarded in 2010, only 9.6 percent was diverted and only 7.7 percent was actually recycled, Sikorski said. In other words, the line for our trailers going to the landfill in 2010 would have been about 1,119 miles long and the line diverted to other destinations would be only about 119 miles.

There are some bright spots in this discouraging recycling picture, however. The work of Shaw Industries, the carpet industry’s largest manufacturer and its biggest recycler, shows the potential for recycling across the entire industry. Shaw has developed a national network for collecting worn carpet and bringing it back to its manufacturing plants in the Dalton, Ga., area, and the company has a use for every scrap so that nothing ends up in a landfill.

Even more impressively, of the 121 million pounds of worn carpet collected by Shaw in 2010, about 85 percent was passed through a unique and highly sophisticated system that literally recycles old carpet into new carpet in a closed-loop process, considered the holy grail in sustainability circles because it eliminates the need for acquiring raw materials.

In a closed-loop recycling process, a material can be chemically induced to reassume its “virgin” state so that it can be reused over and over. Most materials cannot be recycled in this way, either because impurities were introduced during its useful life or because the recycling process weakens it. Instead, the material must be “downcycled” into a product that requires less purity or less strength. That product in turn may be downcyled for the same reason. Eventually the product reaches the end of the line and winds up in a landfill.

Shaw recycles what’s known as nylon 6 carpet fibers in a closed-loop process. The nylon 6 is “upcycled” into the material that is used to make new nylon 6 carpet fibers. This recycled material is indistinguishable from the fresh stock made from petroleum, which Shaw still purchases because it does not have the capacity to recycle all the nylon 6 that it needs.

For Shaw’s 24-by-24-inch EcoWorx brand carpet tiles, both the nylon 6 face fibers and the backing are recycled in a closed-loop process. Forty-four percent of the content of Eco Worx is recycled.

Despite EcoWorx’s “green creds” and the ease of replacing individual carpet tiles when they become irreparably soiled or stained — certainly appealing to anyone with pets or small children — it is not commonly used in residential settings. Designed for high-wear installations such as schools and office buildings, EcoWorx’s short face fibers feel hard in bare feet. In their homes, where many people go shoeless, they want carpeting that is soft and cushiony, “so it feels good to wiggle your toes,” said Troy Virgo, a Shaw executive.

For residential settings, Shaw’s nylon 6 “Anso” broadloom carpeting, which looks and feels like conventional carpet, is a better fit, Virgo said. Twenty-five percent of its content is recycled nylon 6 fiber. The backing for Anso cannot be recycled in a closed loop; instead, the backing is used for other products.

Nylon 6 carpet is not the only type that Shaw recycles. It collects and recycles all types of worn carpeting from all manufacturers, not just its own products.

For example, the nylon 6.6 fibers (not to be confused with nylon 6) in worn carpets are sheared off of the backing, pelletized and sold to other industries that mold them into plastic components. “When you lift the hood of your car and see black plastic parts everywhere, you could be looking at your old living room carpeting,” said David Wilkerson, Shaw’s corporate director for sustainability.

Polyester carpet fibers, which can be made from recycled plastic bottles, cannot themselves be recycled into new carpet fibers. Instead, the worn polyester fibers, along with everything else that Shaw collects and can’t recycle, is shredded and burned as fuel for Shaw’s on-site, electrical power-generating plant. The ash residue that remains is sold to cement manufacturers.

What lies ahead? The long-term challenge for Shaw and the carpeting industry “is to expand our recycling capacity to match our manufacturing capacity so that we can close-loop recycle everything we make,” Wilkerson said.

Recycling all the nylon 6 would be a good place to start. If all the nylon 6 carpeting that’s made in the United States could be recycled into new carpet fibers in a closed-loop process, the hypothetical line of long-distance freight carriers that went to a landfill in 2010 would have been shorter by 440 to 568 miles.

Katherine Salant has an architecture degree from Harvard. A native Washingtonian, she grew up in Fairfax County and now lives in Ann Arbor, Mich. If you have questions or would like to suggest topics for coverage, contact her by e-mail at or