Layers

[salt]

After around 8ish hours in the backcountry the other day, I arrived at my car and took off my shell. Underneath all around me was frost. Literal thick white frost covering at least fifty percent of the coat, arms, torso, everything. I was actually in awe.

I wear a HUK angling wicking base layer, then a North Face Thermoball, its worked for me everytime. I recently added the North Face Apex Flex shell for good measure.

I wasnt cold at all, not one time all day but i had frost on me for sure, i just never noticed. Typically i'll sweat on a trek up but minutes after descent the HUK/ Thermoball are already drying up. The system has worked well but this frost puzzled me. It was like the goretex kept it inside and cold enough to linger or something. I dont know.

Thoughts, advice?

[Makwa]

Did you stop along the way to go fishing?

I've never experienced frost inside my jacket... only in my gaiters which are worn over a base layer tight and then softshell pants. So, the frost forms as a result of moisture venting through the softshell and collecting on inside of the hardshell gaiter where it freezes. Is your outer shell (NF Apex) a softshell or hardshell? I think the Thermoball jacket you're wearing as mid-layer is synthetic insulation, right?

[Makwa]

From what I've read the Apex Flex is a softshell. Check out this review...

https://gearjunkie.com/review-the-no...ll-rain-jacket

The interesting part for me is this though... "For higher heart-rate activity, neither coat is breathable enough for sustained exertion. You will get sweaty, even with the vents open. Think of these as shells to keep you warm and dry, not as breathable activewear."

Seems to me you're getting the frost inside your jacket much in the same way I'm getting it inside my gaiters... the outer shell isn't able to vent the moisture and it's collecting/ freezing there.

[salt]

Yeah again, just need a fresh eye to see it. There's zippers all along this thing. And none of them would've been open. For fact I know they are closed. I have vents on my pants and I always keep them open, I wear no base layer, and have always been warm. Where I'm going with this is. I'm going to open all these vents and see what happens. I'm back out Sunday. I sweat and there are times when I can feel it but never enough to stop and layer down. I've never layered down ever. And I'm always dry by days end. That's why the literal frost was astonishing to see. My only thought was that the material was in fact keeping it cold enough underneath to turn sweat to frost. I wasnt splashing around in waist deep snow by any means. None at all to be clear. I've worn that Apex out twice so far in the HP's. It's half and half now I guess. Vents open, fingers crossed, no frost. As well again though, I was not cold or shivering or anything of the like. Frost is obviously unacceptable but just to say.

[CatskillKev]

I guess what is happening is that the shell itself is getting to 32 degrees or colder, and freezing the humidity inside. This does not mean that the temperature inside is that cold. Opening vents may not avoid it, I suppose. But opening vents will lower the amount of moisture. I don't know where your sweat goes by the end of the day.

[brandtb]

I guess what is happening is that the shell itself is getting to 32 degrees or colder, and freezing the humidity inside. This does not mean that the temperature inside is that cold. Opening vents may not avoid it, I suppose. But opening vents will lower the amount of moisture.

That sounds about right - happens with certain of my outermost fleece layers under certain shells depending on temps/exertion.

[Trail Boss]

See: Dew point. Or in your case it was frost point.

It's the temperature at which (your) vapor condenses to a liquid. It'll become frost if the temperature is below freezing.

This can happen in sleeping bags. Your body's water vapor condenses, and freezes, within the insulation (i.e. frost point occurs within the insulating layer). Over several days, the bag will take on weight and reduce the insulation's effectiveness.

The same thing can happen with clothing in cold weather. Put on enough insulation and the frost point is no longer outside your layers but in them.

Shells with waterproof-breathable membranes can exacerbate the effect because the membranes can impede the flow of vapor. In addition, if you wear enough insulation, your shell's temperature can become the ambient air temperature, meaning below freezing. Vapor will condense on the shell as frost.

One way to mitigate this is to allow your body heat to maintain the frost point outside your insulation. That's a fancy way of saying wear less clothing so you lose enough heat to keep your shell warm and the frost point outside of it.

That means staying much cooler during the hike and being prepared to quickly throw on a layer when stopped (or stopping for much shorter periods). Frankly, it's tricky to get the right balance to match the conditions but it does work.

As an experiment, I ventured to Cascade and Porter when the summit forecast called for -40 F with windchill. During the hike I wore two layers, a lightweight baselayer followed by a polyester shell lined with lightweight tricot (a Rab Vapour-Rise jacket, effectively the same as Marmot's Driclime windshirts). It was definitely on the 'cool' side of things but did keep frost from forming inside the jacket. It formed outside the jacket (visible as white tendrils in the photo).


Frost on the surface of the Vapour-Rise jacket

During my descent from Cascade, I wore a Rab shell with eVent (waterproof-breathable membrane) over two layers (same color as the one in the photo above but not made of the same fabric). I was toasty but by the time I reached the base, frost had developed inside the shell.


Frost on my head but none outside the eVent shell (it's inside the shell)

[FlyFishingandBeer]

Wear less, sweat less, vent more. If you aren't starting your winter hikes with a barely tolerable chill, you're wearing too much. Move fast, and you will warm up quickly. Unless there's a strong risk of being soaked through or I'm in a very exposed area, I typically hike in just my two base layers: A Nike dry fit tshirt and an Under Armour elastane/poly long sleeve tee. Unless I'm in sub zero temps this is enough to keep me at the right temp most of the time, and I'll still have a sweaty back when I take my pack off. I'll layer up to summit, but those extra layers usually come off as soon as I'm back into the trees again.

Feel free to call me a gear snob over this, but IMO Gore-Tex is the only outer layer that actually does what its supposed to do; GTX Pro more so than the other variants. eVent, Membrane, System3, and all of those other proprietary knockoffs never really do what they're supposed to do. They work well for walking your dog or sledding with the kids, but in high output mode, they turn into vapor locks.

[Trail Boss]

Actually, I've had better luck with eVent than with Gore-tex. In the cold conditions I described, all membranes will experience difficulty. They need a pressure differential to drive the vapor through the membrane (without it, the only recourse is direct venting through pit-zips, etc). That's difficult to produce if you're wearing enough insulation to make the inside of the shell as cold as the outside. Plus if any vapor freezes within the membrane's pores, it's game over for breathability and the vapor, having nowhere to go, condenses on the shell's cold interior surface.

[salt]

Well thanks to everyone who chimed in on this. I guess it's unanimous. It's just frozen sweat. I should've scraped it all off and weighed it cause it was a lot, haha. I guess though maybe ill ditch the Apex unless it's crazy cold. Not to mention a nice new coat is out of the budget question for now. I have to make all of it work one way or another. It's odd how you can take two items like this with all the features and hype and still find a way to make it not work. I usually sweat and I usually am aware I should stop and layer up/down but most times I just want to go. Also again to note, I've never been cold to a point where I was scared. I think the Thermoball works fine and dries fast. It's just so light and packs down to nothing so I always feel like it wouldn't hurt to have another layer around. I've seen both the insulated and non insulated versions of the Apex. I like to think that with the Thermoball underneath the Apex I have a homemade insulated version thats waaaaaay better. I'm going to vent it this weekend and see what happens. There's like four or six vents on it and all have been closed since purchase. Although as said, vents won't completely solve sweat and that's clearly what it is. I'll give it another go and hopefully see different results. Tricky business for sure.

[Trail Boss]

As with "Reduce, reuse, recycle.", there's an intended order to FF&B's recommendation to "Wear less, sweat less, vent more."

Wear less so you sweat less so there's less need to vent.

Venting is something you do when there are no other options (you've peeled off as many layers as is practical). Like when my legs get too warm so I roll up my pant legs and unzip my pockets and fly. The resulting convective "chimney effect" produces the desired cooling of limbs and 'things'.




RE: "Frozen sweat". Nailed it!

[Yury]

Before I start unzipping my fly, I remove my hat and my gloves.

[salt]

Right on, everything makes sense. Duly noted and will do. Seems i'll get use from the Apex but more efficiently in other seasons. She's still coming along though, just in the pack. I only bought the thing in the first place because the slogan was "never seek shelter again." I was just so over seeking shelter all the time so I just put my money on the counter. If I do get caught out there i'll deploy the onboard "never seek shelter again" button and hope Neil is hiking in that same area soon.

[debmonster]

I agree with the others that you're wearing layers that are much too warm. I personally would not hike in the Thermoball and carry it more for when you are stopped and need to put on a warm jacket. For winter hiking in the 10-20 F degree range, I wear a mid-weight zip-neck base layer top and a lightweight breathable windstopper softshell jacket with pit zips (Mammut Ultimate Hoody), or the Marmot Ether DriClime hooded jacket with mesh underarm vents. Both weigh around 10 oz. and keep me warm enough for when I'm moving. I know that you said a new jacket is not in your budget, but the Marmot Ether is on sale many places for around $85 (check Campsaver.com or the Marmot website). It's one of the best and most versatile jackets ever made. (I'd also urge you to replace that way-too-heavy 1.5 lb. Apex, but you seem fond of it so I'll let it go. )

[salt]

Well thank you for the advice. I guess I've really been overdoing it with it all. Its really great food for thought. Carrying the Thermoball would most certainly not be a problem. I'll check out the Ether though, I really like the Marmot brand so we'll see. I could probably squeeze that in somewhere. And yes I'm quite fond of it for sure. It even has a fancy morale patch with my name on it so people know it's me. :P

[salt]

Checked out said Marmot. Thanks debmonster Ya just cost me $87! Haha, it's unlike the other pieces I own and seems to be very capable. Add the recommendation from someone who definetly knows and I'm sold. Should round out my collection nicely. No blacks or greys available so my color scheme is gonna be whacked but oh well Thanks for the links and info though. Much appreciated. Very cool piece. Im excited to own another piece of Marmot gear as well. I have a Tungsten 2P tent that's under-used as hell. Love it though. Thanks again.

[debmonster]

Very nice to hear. Enjoy!

[Yury]

I arrived at my car and took off my shell. Underneath all around me was frost.

I wear a HUK angling wicking base layer, then a North Face Thermoball, its worked for me everytime. I recently added the North Face Apex Flex shell for good measure.

Neither softshell nor hardshell work well in real winter. Breathability of Goretex is very limited in cold weather. Softshell is better but it also is not breathable enough.

Non-treated nylon wind jacket is the best option in case you do not have a strong wind.
In case of a strong wind you need a hardshell and accept a layer of frost inside.

You can find a cheap wind jacket in Walmart, Winners, Marshals etc. You should be able to find one with $20 to $30 price.
Such jackets with breathable nylon were almost extinct for about ten years, but they have started making them again in the last two years.

When hiking in such wind jacket you need to have a hardshell jacket in your backpack as a backup in case you encounter a strong wind.
Marmot Precip is a reasonably priced and reasonably light hardshell option.
When hiking in a strong wing I bring an antique/antic MEX Goretex jacket that weights 20 to 25 oz ( I do not remember its exact weight).

[Trail Boss]

I'm not sure there's much utility in comparing the performance of equipment and clothing used over a 100 years ago in polar conditions. At the turn of the 20th century, there were no synthetics only natural fibers and rubber. Even clothing insulated with down wasn't widely employed by expeditions until decades later (for example, Amundsen used sleeping bags made of reindeer fur).

The fabric technologies of yesteryear were limited to what was available and don't represent the best of what's possible today. That's not to say they didn't work (they did) but modern fabrics offer advantages (less weight, or bulk, or faster drying time, or cost of production, or wind/water resistance, etc).

[CatskillKev]

Trail Boss said "The fabric technologies of yesteryear were limited to what was available and don't represent the best of what's possible today. That's not to say they didn't work (they did) but modern fabrics offer advantages (less weight, or bulk, or faster drying time, or cost of production, or wind/water resistance, etc)."

But, Yury said that people are taking a modern look at cotton in extreme cold. Since you're being a scientist here Trail Boss, any thoughts on whether the breathability of cotton could work in a hooded heavy cotton garment, climbing with much exertion through the snow-laden trees of the Adirondacks, in extreme cold?

[FlyFishingandBeer]

People will always try to reinvent the wheel in various ways. In the world of competition shooting, revolvers are making a hipsteresque comeback, and people are concocting all kinds of reasons for why they're using them over modern autoloaders. There's reasons why our nation's best when it comes to "practical applications" aren't using revolvers.

Translate that into modern mountaineering in extreme climates. There's a reason why the best in the world are using this https://project-himalaya.com/dispatc...mmit-kevin.jpg and not this
https://uberflip.cdntwrk.com/files/a...BiMDYxOWE%253D

For several years I lived in both interior and coastal Alaska, spending a lot of time hunting, back country skiing/snowboarding, and a good deal of hiking in the Denali area. I'll strongly attest that when it comes to extreme cold, cotton is not the fabric of our lives.

[buddy]

I've been using the Dickies 60% polyester 40% cotton cargo pants for years now. The cotton seems to sponge moisture from inner layers and disperse the moisture over a wider area in the polyester matrix allowing for faster drying than unblended synthetic fabric does, it gets the moisture to the surface where drying takes place, the wetter it is the better it works. They are indestructible, offer bullet proof protection for bushwhacking and the cargo pockets are secure and convient for easy access to maps, compass, or gps. At about $38 they are worth a try.

[Trail Boss]

I've been using the Dickies 60% polyester 40% cotton cargo pants for years now. The cotton seems to sponge moisture from inner layers and disperse the moisture over a wider area in the polyester matrix allowing for faster drying than unblended synthetic fabric does, it gets the moisture to the surface where drying takes place, the wetter it is the better it works. They are indestructible, offer bullet proof protection for bushwhacking and the cargo pockets are secure and convient for easy access to maps, compass, or gps. At about $38 they are worth a try.

60/40 poly/cotton blend in winter? Like, winter in Florida?

Cotton wicks moisture which is what makes it ideal for hot weather. Moisture may be sourced from only one point of contact but the cotton fabric will spread it over as much surface area as is available. That's ideal for convective cooling in summer. It's not ideal in cold wet weather because you don't want convective cooling. Cotton absorbs water into its fibers which aids wicking via capillary action but retards drying. In contrast, most synthetic fibers don't absorb moisture; the moisture only surrounds the fibers. That reduces wicking but aids in drying.

"... it gets the moisture to the surface where drying takes place, the wetter it is the better it works .."
It's useful to examine this statement in isolation. Given two identical pairs of 60/40 pants, one dripping wet and the other just damp, "the wetter it is the better it works" claims the sopping-wet pants will dry faster than the only-damp ones. It suggests there's some "free energy" coming from somewhere in order to evaporate the extra water in the sopping-wet pants faster than the damp ones.

[CatskillKev]

To be fair, "the wetter it is the better it works" does not necessarily have to compete with itself in a dryer version of itself. It just has to compete with some other fabric in the same sopping wet test. I think that is what buddy meant.

[Trail Boss]

Even he meant it the way you suggest, it's still unsupportable by science.

Use the polar-opposite corner-cases as a thought experiment. Pit wet, 100% cotton jeans against wet, 100% nylon pants. His comment suggests 'the wetter it is the better it works' will magically make the wet jeans dry faster than the nylon pants ... despite the fact the cotton jeans are able to absorb and retain far more water than nylon. You only have to line-dry these two pairs of pants to discover the jeans won't dry faster (... a more comfortable test than trying to wear-dry a soaking-wet pair of jeans).

If we're looking for "fairness", 60/40 blends *are* durable .... and it's the 40% synthetic that's responsible for it. The cotton provides greater comfort against the skin. It also adds some bulk to the fabric which blunts the thrust of brambles and branches (like buddy said, good for bushwhacking). Its other properties become drawbacks in cold and/or wet conditions.

[CatskillKev]

Yes, not trying to be a scientist here. You make a valid point Trail Boss, from what I can tell. His science may not be supportable.

[Neil]

Haven't read the entire thread so excuse me if I'm redundant.

Of late I've been wearing a Rab eVent jacket on bushwhacks where , eventually, everything seems to gets soaked. I've tried various combinations of fabrics on the upper and lower body but getting soaked is the condition you just have to suck up. Soaking wet legs, soaking wet torso. But, when I removed my wet Rab jacket on top of McNaughton a few weeks ago I was very surprised in that the inside was quite dry. I swapped out my base layer shirt and put on some heavy-duty insulation for about 15 minutes before it was time to go. The jacket's outside was now frozen stiff but when I put it back on my base layer remained fairly dry for the long hike out. As for anything with cotton in it I would never take it on the recent bushwhacks I've been doing.
However, decades ago when I used to winter-camp in -40 we wore 60-40 jackets. It was the latest and greatest tech gear. We traveled slowly so as not to sweat and in the very dry cold air the fabric did the job very well. Our under-layers were 100% cotton. No issues there either but it must be pointed out that what we did was nothing like bushwhacking peaks in the Dacks.

[CatskillKev]

But is it possible that a heavy cotton hooded jacket would perform in the snow-laden trees on an extremely cold day? I think its possible. Or would the untreated nylon be the best? Looking for breathability here. And using the bitter cold as the dryness advantage. Just trying to see if there is an answer to the soaking wet legs, soaking wet torso, and using the bitter cold as an advantage.

I guess the question is, will the cotton shed very cold snow all day long?

[Trail Boss]

If you can crank out enough heat to always keep the snow melting and evaporating then you could probably wear most anything, including chainmail armor.

Practically speaking, we don't (or can't) produce that much heat so the shell can absorb water from melting snow and/or our sweat (especially in the fabric's creases, one's shoulders and the area between one's back and the pack). What happens next is an important differentiator.

If the sodden fabric loses its water-resistance, now you're facing not just convective but conductive cooling (i.e. you get wet from melted snow). However, if all it does is 'wet out' on its surface then it just takes on a little bit of weight, loses some (or all) breathability but remains water-resistant (like Neil's eVent jacket). It may not be optimal but at least you know you're wet exclusively from your own warm sweat and not the addition of unlimited amounts of melt-water. That's far more protection than a seeping nylon or cotton jacket can provide.

FWIW, (when I was still able to hike) I experimented with wearing a simple nylon shell to maximize breathability, shed light snow and a little drizzle. It works fine if you pump put enough heat to keep drying out the jacket. However, when the intensity of the wind or rain or melting snow tipped the balance towards cooling/soaking me, I'd throw on my eVent shell.

In my current avatar, that little bit of frosted red fabric you see is my Marmot Trail Wind Hoody under my Rab Momentum (eVent) jacket. I was ascending Algonquin in ice-mist and, somewhere past the Wright junction when the conditions turned nasty, I threw on the eVent shell over the nylon Hoody. I like the combination because of its flexibility and extended comfort range. Weight isn't an issue because the Hoody is like 6 ounces and the eVent shell is 12. The combination is less than one *dry* cotton jacket.

[salt]

Right on, thanks for the link. Definetly worth a look. I'd never even known of them before. After a quick glance, lots pf selection, reasonable pricing. We'll see, thanks again.

[Yury]

Trail Boss, can you compare Rab Momentum vs. Marmot Precip?
Is there any significant difference?

[Trail Boss]

I have both. However, the Precip version I have is very old (~15 years) whereas the eVent jacket is ~7 years old. Not exactly a fair comparison but the eVent jacket has much better vapor permeability. Both jackets are equally wind and rain-proof.

For a fair comparison, I'd need to try a late-model Precip jacket. However, I can't currently justify buying one. I have Precip rain pants (purchased about 7 years ago) and, the few times I wore them, they were far less 'breathable' than I'd like them to be (certainly far less breathable than regular pants). However, they're wind and rain-proof and I paid very little for them.

Based on testing one can find posted elsewhere on the Internet, eVent and the latest version of Gore-Tex still lead other membranes (for vapor permeability).

[buddy]

I'm not suggesting that cotton alone is better than synthetics for drying, in reference to wet blue jeans compared to a wet synthetic drying on a line, I'm suggesting that the blend is better and only in reference to single layer pants usually but not always over a synthetic base layer. The cotton and polyester need to be blended in order for the polyester to work as a matrix for the cotton to wick and disperse the moisture over a larger area for faster drying. This is true for dispersing moisture from external sources as well. I find that they are generally dryer and warmer than the synthetic materials I'm familiar with. It's all about increasing the whetted surface area for a given amount of moisture to be dispersed. I do not have any scientific studies, with control groups and all that, but I do have a few decades of winter back country experience and have found that the performance of the poly/cotton blend pants to be superior to any purely synthetic material. I switched about 5 years ago and there is no going back for me. I think if you tried the Dickies blended cargo pants you would love them, especially in winter.

[Trail Boss]

"The cotton and polyester need to be blended in order for the polyester to work as a matrix for the cotton to wick and disperse the moisture over a larger area for faster drying"

Cotton fabrics need no "polyester to work as a matrix for the cotton to wick". Cotton alone does an excellent job of it. Try this at home: hang jeans and the 60/40 Dickies pants so the very bottom of the pant-legs are submerged in separate buckets of water. Come back in an hour and you'll see the jeans had no trouble drawing the water to mid-calf and higher. I'd wager they'll do a better job of it than the 60/40 blend.

I'm old enough to remember 60/40 blends being used in *water-resistant* parkas (Jansport made some nice ones). The theory behind it was the cotton would absorb water, swell up around the polyester threads and make the whole thing more water-resistant. Yet more magical-thinking regarding the mystical marriage of cotton and nylon. The synthetic component makes the fabric lighter and more durable and not much more than that.

I'm glad the Dickies pants work for you but I'll stick to what's worked for me in the High Peaks for the past 7 winters. My soft-shell pants shed snow like greased seals. They're made of 93% nylon and 7% spandex. They have 4-way stretch, breathe well, have a peach-fuzz interior that feels good next to skin (I rarely ever use long-johns) and are remarkably wind-resistant.

Have you ever met retired DEC Ranger Pete Fish? If you do, ask him for his opinion about cotton in winter. It'll be fun.