Gore-Tex is a trade name for a breathable, waterproof, and windproof laminate added to clothing and shoe fabrics. The ultra-thin layer(membrane) is bonded with heat and pressure into a coated outer layer that blocks liquid water while allowing water vapour to pass through. The material, sourced from various materials such as cotton, polyester, and viscose, is designed to be lightweight and waterproof, making it perfect for outdoor clothing, footwear, and accessories.
Since the 1970s, Gore-Tex has been manufactured from a stretched-out form of polytetrafluoroethylene (ePTFE), a type of plastic and a derivative of Teflon. The Gore-Tex layer is most commonly added underneath the upper fabric layer of a garment. The fabric membrane contains millions of tiny holes per inch, and each of these holes is far too small to let through even the smallest water droplet. However, water vapour consists of much smaller particles than liquid water, allowing vaporised sweat to pass through GORE-TEX, resulting in excellent breathability. In addition to the fabric membrane, manufacturers must use tape to cover the seams and utilise specialised seam-sealing machinery to ensure a proper seal.
After finishing the garment using Gore-Tex, the manufacturer must send the item to W.L. Gore for certification. The garments undergo rigorous testing to ensure resistance to abrasion and flex, durability in extreme temperatures, and comfort in heavy precipitation. Footwear is subjected to additional tests, including hundreds of thousands of steps in a water bath to check for leaks and proper moisture-wicking performance.
Starting in 2025, most Gore-Tex products will now be made from expanded polyethylene (ePE) instead, as ePTFE contains PFAS (per- and polyfluoroalkyl substances). The ePE membrane, on the other hand, is PFAS-free, including the water-repellent DWR impregnation, which is better for the environment.
Challenges & Environmental Impact
Gore-Tex is made from polytetrafluoroethylene (PTFE) that originates from fossil fuel; the production process is energy-intensive and requires specialized technologies and the associated greenhouse gas emissions during production. Currently, there is no effective recycling process to separate these materials, and they are not biodegradable.
The products are durable and designed to last, both in terms of wear and tear and the number of washes, which contributes to a lower environmental impact compared to replacing them frequently. The company also offers repair services to guarantee waterproofing and extend durability.
The ePTFE membrane uses PFAS (per- and polyfluoroalkyl substances) to repel water and dirt. Due to their extreme resistance in the environment, PFAS are considered “forever chemicals.” PFAS are synthetically produced, exist in several thousand variants, and have been linked to, among other things, being carcinogenic, hormone-disrupting, and having a negative impact on the immune system and fetal development. Because they are long-lived and can spread through air and water, researchers have found them in places where they have never been used, such as Antarctica.
To remain effective, Gore-Tex fabric must be treated regularly with durable water repellent (DWR), a toxic chemical spray that wears off over a few years. While DWR is not necessary to keep Gore-Tex waterproof, this substance keeps water off the fabric’s surface, allowing breathability. Nowadays, PFAS-free DWR impregnation is available, but the older version is still used, as it is considered more durable.
PFAS and microplastics can leach out during manufacturing and use, contaminating soil and water and harming wildlife and human health.
Sources
Wikipedia – Gore-Tex 
Sewport – Gore-Tex Fabric
Gore-Tex – Next generation Gore-Tex products with ePE-membran
Gore-Tex – Common questions
Naturskyddsföreningen – What is PFAS?
February 2025 TÄNKOM | Revised September 2025, RETHINK
