A pair of jeans worn through at the knee usually ends its life in a landfill bag.
In Chandler, Arizona, it can end up on a conveyor belt instead.
Zippers get pulled.
Buttons get stripped.
What is left gets shredded into a soft blue cloud.
So what actually happens to all that cotton once the belt starts moving?
Shredding turns worn denim into loose cotton fiber in minutes
The plant belongs to a Chandler manufacturer that has spent decades building insulation out of recycled natural fiber rather than fiberglass or foam. Old denim arrives baled and compressed, gathered through a nationwide donation program. Hardware comes off first, and only then does the denim go through fiber processing and get formed into insulation batts.
Once the denim is clean of metal, it is pulled apart into raw cotton fiber, the same basic material the jeans started as before anyone dyed or stitched them. The company engineered a process to treat those recycled denim fibers for fire retardancy and mold inhibition and thermally bond them together into finished batts.
The rolls look a great deal like fiberglass insulation, minus the itch. The manufacturer says the product has no fiberglass itch, contains no chemical irritants and requires no warning labels compared with traditional products, and that it takes a minimal amount of energy to manufacture, which is the basis of its low embedded energy pitch.
More than 4.5 million donated pieces have fed two decades of collection
Since the denim drive began roughly two decades ago, Cotton Incorporated reports that more than 4.5 million pieces of denim have been collected. Over 2,290 tons of textile waste have been diverted from landfills, and more than 9 million square feet of insulation has been manufactured. That is textile waste measured in the thousands of tons rather than the millions.
The net is deliberately wide. Any denim apparel counts, jeans, jackets, shirts, skirts, as long as it is 90 percent cotton or greater, and it can be ripped, stained, embellished or even scraps, provided it arrives washed and dry.
A share of every year’s output is given away rather than sold. A portion of the insulation is distributed each year to help with building efforts across the country, including organizations such as Habitat for Humanity. One partner brand’s collected denim supplied 130,000 square feet of the material for a Hurricane Harvey rebuild effort run by All Hands and Hearts.
Retail bins at major chains keep worn denim moving through the pipeline
Clothing chains do much of the collecting. Buckle was the program’s only retail partner accepting donations early on, and the roster has grown since. Madewell has collected more than 1 million pairs of jeans, while Abercrombie & Fitch has gathered unwearable and scrap denim at its global home office since 2014. A former car plant in Elizabeth, South Australia, found a different kind of material recovery inside its old paint shed, and the denim program runs on similar logic.
The barrier to entry is almost nothing. A shopper drops a worn out pair into a bin at a retail counter, and that single transaction is the first link in the chain. Because the fiber only needs shredding and rebonding, color, brand and decade barely matter. The program now also accepts the denim liners used in meal kits, and sends recovered fiber into pet bed inserts and thermal packaging as well as building insulation.
Batts rated at 80 percent recycled cotton compete with fiberglass on price
The batts are made from 80 percent recycled cotton denim, with the manufacturer citing acoustic and thermal performance in easy install batts. Ownership changed recently: Carlisle Companies announced in June 2025 that it had acquired Bonded Logic, and that UltraTouch joined the Henry brand.
The sales case rests on what is absent. The product is promoted as environmentally safe, with acoustic and thermal performance and without carcinogenic warnings, formaldehyde or chemical irritants, and the program has claimed 30 percent better sound absorption than fiberglass, a manufacturer side figure rather than an independent test result.
Consumer donations are only part of the feedstock. The new owner says the insulation repurposes more than 500,000 pairs of jeans per month and diverts 20 million pounds of denim from landfills annually, far more denim than donation drives alone deliver.
14.5 million tons of American textiles still went to landfills in a single year
The gap between what is collected and what Americans discard stays wide. Some 14.5 million tons of textiles were landfilled and incinerated in 2018, clothing being the main source, according to the Environmental Protection Agency, and less than 1 percent of used clothing is recycled into something new.
Most worn out clothing in the United States, denim included, still ends up buried rather than shredded, largely because there is no bin on most curbs for it. The Arizona model shows the material can be reused efficiently, but not yet that it can be collected at anything close to the scale Americans throw it away.
Still, every bale that reaches the plant is cotton that will never need to be grown, irrigated or dyed again. A pair of jeans that outlived its last wearer gets to keep someone warm anyway, inside a different kind of wall, the way retired school buses get a second working life somewhere else entirely.
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