Breathability of different fabrics

Yeah, good luck finding the info. — apparel makers disclose mostly verbiage hype (Gortex and Sierra Designs come to mind, but they are obviously not the only ones) with precious little stats — and then only in a way that precludes comparison across the board! :(

As for “sauna fabrics”, I believe that’s a term used by BackpackingLight, for windshirts like the old GoLite ones made with “Wisp” fabric. This very lightweight fabric has a thin PU coating, making it fairly rain resistant but barely breathable. In 2005, GoLite switched to a different, more breathable fabric that doesn’t have the coating — called the “Wisp HP”.

Right here at BPL – which does do some pretty nice research – this was on the editorial calendar a couple years ago. It got moved a couple times, but then dropped. You can sift a lot of it out of articles on windshirts and stuff like that, but there’s never been a comprehensive objective report done that I’ve found. I have done informal ones – I’ll post when I get a chance….

I’m glad others have found it difficult to find hard facts. But BPL might have some actual numbers to support the coining of the term “sauna fabrics” compared to others. Anyone?