Arc’teryx TWEAVE 520e, 518c, LF544 and similar soft shell/wind jacket materials: opinion sought

CFM isn't going to have much effect on rain protection. DWR quality will. A greater CFM might (emp. might) allow more body heat transfer which can dry a windshell from the inside and keep it from wetting out over multiple hours of drizzle.

The main problem with those fabric options, and indeed with most "soft shell" fabrics, is the spandex content. Spandex likes water a lot more than polyester or nylon, and thus I'd estimate once those fabrics get wet, they'll be real wet for a while.

IIRC Tweave was built for the military, with abrasion resistance high on the spec sheet. In the windshirt and soft shell realm using the lightest fabrics appropriate for the task is desirable, precisely because once they get wet they can get dry again fast.

That's interesting about spandex David, with a moisture regain of only around 0.6 to 1.2% on average, you would think it wouldn't hold moisture that much. This is much lower than nylon, and more comparable to polyester and acrylic.

Wonder if the stretchy nature has something to do with it?

Klaus, have you researched or looked into Paramo or Furtech type WPB systems? Unfortunately these are only found in Britain currently.

Basically they are like a fairly breathable windjacket layer combined with a light'ish weight, thin half fleece liner. The liner has smaller fibers on the outer surface (fuzzy, very short pile–probably brushed) and larger fibers (smooth) on the inner surface, which physically tends to cause water to keep repelled to the outer part. They do run a bit warm and are best for cooler weather.

They are not truly waterproof in the technical, or usual sense of the term, but work well enough for a lot of conditions. I don't have a lot of experience with these systems so far, but so far so good. I'ved used a 2012 Houdini in combo with one of their "pump" liners.

My experience so far suggests that the shoulders where the straps from a pack are, are the weakest link in these systems (get more wet there). I made a sort of a half, minimalist silnylon poncho to deal with this and to cover my pack at the same time.

The company claims for both the 520e and 518c: "In the event that the garment does get wet, the fabric will hang dry completely in less than 45 minutes, at standard room temperature."

On most occasions I will ditch my hard shell and just take my wild things wind shirt in epic. It breaths better than any hard shell and is sufficiently water resistant for my purposes. I did seal the shoulder and hood seams. I also own a black diamond single wall tent in epic and haven’t experienced the problems in rain that others complain about.

As a point of reference, I’ve been out in heavy rain and prolonged rain, but I haven’t been out in multi-day heavy prolonged rain in either the wind shirt or the tent.

As far as soft shell fabrics go, while I don’t have an issue with soft shell pants in the rain, I prefer the epic fabric wind shirt’s performance to that which I have experienced wearing various soft shell jackets.

Justin, I've seen rather different numbers for spandex moisture uptake, and my anecdotal experience (and limited empirical experiments) supports something much higher than ~1%.

To function properly, Epic needs to be cleaned. I think most of the leakage in the old BD tents was the result of this.

Justin,
Thank you for the Paramo pointer. I spent a few hours reading up. It appears very suitable to my climate, the Canadian Maritimes. Their "Helki" jacket interests me most but Hobbit sizing appears to be a common problem so a Cioch custom order like you did seems approproate. I also found your older post combining it with the Houdini. I'd love to read your experience reports when you have them.

Part of custom sizing is to get a coatlength rather than the short jacket length that's in fashion. For walking about, coat length (going about to the bottom of the crotch) is far more useful for walking about. With that, even in cold rain all I need is marino long johns and DWR treated Columbia nylon pants, plus gortex gaiters.

Hi David,

I'm wondering if it's the hydrophobic level of the material itself, or possibly more of a structure issue?

What i mean is that if individual fibers of spandex are more inherently fibrous or micro porous in nature, then it might hold more moisture than another material with a similar hydrophobic level of the material itself, but which is more solid in nature?

Don't know if this is actually true or not, just a thought, when thinking about why this should be the case. In any case, the end result is the same, it soaks up more moisture than most other synthetics.

Hi Klaus,

Your welcome. When i do some more testing, i will try to remember to write down more specifics and share it later.

I was less impressed with my wife's knock off "pump liner" that i had tried a little while back in combo with the houdini than with my Cioch pump liner. However, it may be because my wife sweated it out on a trip previously, that it reduced the effectiveness of Nixwax DWR treatment some? I hadn't washed it after that trip.

I got a little wet on the back of the arms with it. I'm thinking of also silicone treating the seams of the Houdini to also help with any issues.

As a side note: David, are you sure about that higher number ? Because I mostly find something about 1,3 %. Never higher.