At the heart of Gore-Tex is a super-thin membrane that is waterproof, windproof, and breathable, with over nine billion pores per square inch. These microscopic pores are 20,000 times smaller than a water droplet, but 700 times larger than a water vapour molecule, which means perspiration can escape, maximising breathability.
The construction of the garment is as important as the fabric itself, because even a completely impermeable material is useless if the garment’s seams are not properly heat sealed. It is this finishing process that must pass Gore’s demanding quality control regime, standards that must be met before a product can be released onto the market.