Originally Posted by
lil brown bat
Goretex isn't a waterproof fabric. Any Goretex garment that is waterproof is made so by application of a durable water-resistant (DWR) coating, which eventually wears off (or goes a lot faster if you don't launder it properly). I'm guessing that with something like a glove, with a lot of seams and many many chafe points, a DWR coating doesn't last long under the best of conditions.
This isn't totally correct. Believe it or not, the DWRs primary role on a Goretex garment is to aid in the breathability by preventing the outer face fabric from becoming saturated with water. Once saturated, this outer fabric would no longer allow the water vapor created by your sweat to pass through, thus causing increased condensation, which makes it feel as though your jacket is no longer waterproof.
The rub of Goretex though, is that even with the DWR working full-on, it's still a flawed material as far as breathability is concerned. In order to avoid contaminating the stretched PTFE layer (Teflon) with oils/dirt/etc, which allows for water transfer and shortens lifespan, Gore added a thin (or not so thin with older Goretex) layer of PU (polyurethane) to the PTFE layer, thus negating the whole beauty of a stretched PTFE layer.
Enter eVent (and a couple other companies), which figured out a way to eliminate the need for the PU layer, thus providing much better breathability with only a small decrease in waterproofness. This said, all rain jackets, regardless of the waterproofing agent (except silicon impregnated nylon), will need to remain treated with DWR to stay breathable, although not to remain waterproof.
Whoa, sorry for the lecture there.