The Science (and History) Behind Waterproof Clothing

Keeping the rain off and staying dry has been a universal human challenge for as long as we’ve been around. The indigenous peoples of Mesoamerica were the first to waterproof clothing, using sap extracted from rubber trees—a technique quickly adopted by the conquistadors after their arrival. But raw rubber was far from ideal: it stiffened in the cold and turned sticky in the heat. For centuries afterward, heavily oiled—often foul-smelling—fabrics became the standard solution for sailors and explorers.

It wasn’t until 1823 century when Charles Macintosh — yes, the man behind the mac coat — sandwiched a layer of rubber between two layers of woven fabric, marking a major leap in waterproofing technology. Two decades later, the process of vulcanisation (adding sulphur to latex) stabilized rubber, and macintosh technology has remained practically the same ever since.

Unfortunately, garments waterproofed with rubber come with two major drawbacks: they are heavy and completely non-breathable. Neither of these was a problem for the indigenous Yup’ik hunters of the Polar region. Using the intestinal membranes obtained from marine mammals, they created the world’s first extra-light and breathable protection against humidity — long before man-made membranes were even an option. Yet this ingenious Arctic technology remained bound to its place of origin, never spreading across the world.

Since its invention in 1938, polytetrafluoroethylene has found use in everything from waterproof garments to non-stick frying pans. In its raw form, however, it was no more breathable than rubber, leaving people with little choice but to sweat through the rain. That changed with the accidental discovery of Gore-Tex—a microporous structure that is light, breathable, and, most importantly, waterproof. Today, Gore-Tex is manufactured from a slightly modified compound, but its fundamental design remains the same: a membrane sandwiched between protective fabric layers. To further boost performance, most garments also receive a DWR (durable water repellent) coating on the outer surface.

Today’s waterproofs come in a myriad of designs tailored for vastly different applications:, ranging from ultra-lightweight, minimalist jackets to insulated hardshells. For prolonged use in harsh, wet conditions, combining a waterproof membrane with synthetic insulation is the best choice. Brands such as Arc’teryx, Eddie Bauer, and Mountain Equipment choose Climashield® continuous filament insulation which performs even when wet, should the membrane fail — which is unlikely but it can happen.

Most commonly, when the DWR treatment wears off, moisture saturates the outer fabric of a garment, causing its breathability to drop drastically. As heat and sweat build up inside, the wearer can end up cold and clammy. Even in this scenario, synthetic insulation offers a safeguard: retaining its loft when wet, thanks to the proprietary AquaBan technology Climashield® continues to provide warmth in any conditions..

Although today’s waterproof jackets combine cutting-edge membranes with advanced synthetic insulation, their purpose has remained the same for millennia. Staying warm and dry has enabled the rise of cultures, fueled exploration, and continues to keep us safe and happy in the great outdoors, no matter the weather.