interesting … looks like goretex is going light weight by design …
http://www.outdoorsmagic.com/gear-features/new-gore-tex-fabric-launches/7530.html
Gore-Tex Active Shell, a new fabric which Gore says is the most breathable waterproof material the company has produced.
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Gore says the fabric is 'more breathable than other waterproofs and as breathable as calendared textiles', which is a pretty big claim. In tests it has an RET of around 3, but all you need to know is that's comparable to some soft shell fabrics.
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It's all been tested using sweating brass dummies in a lab and Gore is confident it works. Oh, and to save weight and up breathability, face fabrics can be no thicker than 40 denier – to put that in perspective, ME already uses finer 20D face fabric on its FireFox Pro Shell jacket.
It should be at a similar level of breathability to Gore Windstopper says Gore.
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On top of that, a closer fit is more efficient because air gaps in your clothing system are an effective obstacle to vapour transfer.
The spin off from that, is that Gore has laid down guidelines for garments made from Active Shell, stipulating a close cut, few pockets and no fabric pocket linings, always mesh and designs using as little taping as possible like Haglöfs two-panel Oz Pullover.
There will be maximum weights for garments made from Active Shell too, for trailsport use – no hood – jackets will have to be 300g or less and for alpine, hooded use, 400g. The medium test jacket we brought home from Plas y Brenin tips the scales at 230g, so all good on that front we reckon.
