Mountain hardwear airmesh: Active Mesh Teijin Octa midlayer

[wander lust]

New active insulation range from mountain hardwear:

https://www.mountainhardwear.com/p/mens-airmesh-hoody-1949521.html?dwvar_1949521_color=442&pos=0

Has anyone tried it yet?
Seems to be similar to alpha direct and should be more durable.

[Stephen Seeber]

Strange you should ask.  I purchased one over the weekend from REI.  I did my wick/dry test on it.  For comparison, I simultaneously tested an old, well used, Patagonia Capilene Midweight.  The result:  the Capilene shirt wicked 2.88 times more water than the Airmesh,  the Capilene shirt supported evaporation of 10 times the water supported by the Airmesh.  So, once water wicked into the Airmesh, it was much slower to evaporate than with the Capilene.  The Airmesh is, qualitatively (based on IR images only, real R-value was not measured) a little warmer than the Capilene midweight.  It is much lighter (29% less weight.  (This did not reflect the extra zipper weight in the Airmesh, so, it is actually better than 29%)  Their claims about warmth to weight being excellent are correct.  However,  it is not clear that it is better than Alpha Direct in terms of warmth, warmth to weight or durability.   Without further testing, I suspect warmth and warmth to weight will be better for Alpha Direct.  I suspect better durability for Airmesh-it will be harder to snag on objects. Again, I don’t know for sure for either fabric.  So far, I have had no durability issues with my Alpha Direct garments.

[wander lust]

Thx Stephen.

Mountain Hardwear did supply me with the weight of the hoody and crew in Size M:

Hoody 5.2oz

Crew: 3.9oz

[Matthew S]

Stephen,

I have a hypothesis about Alpha and possibly the new Teijin material. I think wicking isn’t as big of a deal in Alpha (I find it very hard to get alpha to become laden with sweat.) The reason why may be that Alpha just sits on top of your skin. Yes, some of the material touches the skin, but it’s a super light “fluffy” material. So, when liquid sweat first rises to the skins surface, it has an unencumbered chance to phase change from liquid to vapor states. In traditional fabrics, the liquid sweat almost immediately hits the fabric and is wicked. In Alpha (and now Teijin?) the liquid goes to vapor and wicking can mostly be skipped all together? This would be very good, because basic chemistry tells us, when matter goes from one state to another, extra energy is required. In this case, that evaporative energy change has a cooling effect on the skin. What are your/others thoughts?

I have a AirMesh on the way. 4.7oz for size large (according to the text reviewer,) the apparent depth of the loft, and the air hole density sounds like it’s worth investigating.

[Roger Caffin]

Talking about a Teijin material is not very helpful. Teijin is a global company with many arms and with global sales in the billions of dollars. I am sure they can make good fabric, but one does need to be a shade more specific about which material.

Fwiiw, I believe Teijin own the Pertex brand, and have done so for many years.

Cheers

[wander lust]

The material used in these garmets is called Active Mesh Teijin Octa. Unfortunately Mountain hardwear did not provide me with any information in regards of fabric weight…

[Stumphges]

Mathew, I follow you, and I think you might be able to say the same thing about Brynje fishnet baselayers. And then, by extension, you might say the same about Roger going barechested under his taslan windshirt.

I’m not sure, but I think that, while moving and generating heat, it’s all well and good to evaporate sweat from the skin, but isn’t the old argument in favor of wicking that, if we suddenly stop, our wet skin will “flash off” or whatever and chill us to the bone. So if we’re wearing Power Dry, that evaporation happens further from the skin, or something…

And from there, if the baselayer is wicking, wouldn’t we want the next layer to wick too, may as well keep the moisture moving toward the surface? This was the principle behind pile/pertex (Buffalo), wicking mesh/Pertex Equilibrium (VapourRise), wicking mesh/polyester microfiber (DriClime) and even Paramo (where capillary depression, rather than capillary action, is supposed to do the work). Of course, all these fabric combos were meant to deal with internal and external moisture – all were meant to wick perspiration and rain ingress away from skin and towards the surface. “The original softshell concept.”

So while it is great that the “softshell” concept is being reinvented – afterall, what is a layer of Alpha with a winshirt sewn to it, if not a softshell? – I can’t help but think that something is being lost. Are we going from a combination of wicking insulation + windshell fabric that can keep the wearer dry and warm during all-day mild/moderate rain whilst active to something that cannot, all in the name of saving 4 ounces? Is “active insulation” just a lighter version of “softshell but without the moisture management function?”

I don’t know. It could be that super-light, fuzzy, airy neofleeces like Alpha actually do better in such conditions than wicking fabrics of yore. After all, Alpha was designed to keep soaking wet soldiers warm…

So Alpha is cool, but would be be cooler if it also wicks?

Anyway, Mountain Hardwear/Teijin make some moisture management claims about this “ActiveMesh” OctaLoft stuff (“Made with a unique active mesh, consisting of hollow, tube-like fibers with radial extensions that absorb sweat, quick-drying capabilities are at its highest, supporting insulation and heat-shielding properties to keep you cozy in the coldest conditions…”), and that’s probably why Stephen gave it a wicking test.

Roger, those who’ve read Stephen’s article on active insulation will recongnize the “AirMesh” in this Mountain Hardwear garment as being substantially similar to the material used for the lining of the Arcteryx Proton FL, a jacket that Ryan J. has touted in several articles, and that Stephen tested above. An interesting point, though, is that Arcteryx put it mesh side toward the skin, while Mountain Hardwear has put it the other way around. Apparently, it doesn’t matter which direction the “tube-like fibers with radial extensions that absorb sweat” are pointing.

BTW, Roger, why do you eschew wicking baselayers?

[HkNewman]

Felt some of it at an REI a couple days back.  The outside of the fabric is basically a mesh shirt, like a ‘90s era running shirt with visible perforations, and then the interior-brushy insulation layer.  The inner layer is very soft yet “brushy” so I can see it being next to skin if need be.  It could also be worn on top of a thin shirt, but would definitely look at sizing if that’s the case as it seems a bit “fitted”.

I’d personally want to wear some sort of shell with the stuff if around any sort of vegetation that could snag that outer layer YMMV.

[Roger Caffin]

Hi Stumphges

BTW, Roger, why do you eschew wicking baselayers?
But we don’t.
In the snow we would normally have some sort of thermal baselayer on, and that does wick. We wear it when we need it.

Outside of snow conditions we do not have anything under our Taslan windshirts (or smocks) for the very simple reason that we don’t need anything. The single layer of Taslan keeps us warm enough while we are walking under most any conditions. Caveat: if it is decidedly frosty in the morning we might wear a thermal baselayer as well for the first 15 minutes, but then we take it off – BEFORE we start to sweat.

Incidentally, the Taslan fabric is not smooth. It is made from an ‘air-textured fibre’, which means the surface is just slightly ‘rough’, and it does not stick to the skin. On the other hand, the fibres which do touch the skin will wick some moisture away.

But there is another very important point here which has been glossed over. Very bluntly, and just going on my experiences here at BPL, most Americans are over-dressed, sometimes seriously so.
People complain that their jackets do not breathe well enough, and that they need pit zips etc to get rid of the sweat. That is not the problem: they are just over-dressed. They should not be sweating in the first place.
Take some of the clothing OFF!

To be sure, we might be a bit cool for the first 5 minutes of walking, but we KNOW from experience we will warm up quickly and then be OK.

The only time one could justify having sweat on your body is in very hot weather when your pack is blocking the loss of sweat from your back. Frameless silnylon packs pressed against your back will be bad: no circulation at all. So-called ‘air mesh’ suspension, or a well-designed frame which mostly stays OFF your back, is what you need in hot weather.

<here endeth the sermon>

Cheers

[Russ W]

Roger,

Mostly agree with everything you said….

However, I can work up a full sweat in subfreezing temperatures in minimal base layers and wind protection. Exerting energy, I sweat. As minimal as I can get with low temps, my base layer will be soaked. I can take off that base layer and hold it horizontally in full frozen mode, and have done so.

Some folks at the gym just glisten…me, I drip in profusion.  Could probably hike commando and sweat.

Sorry about your sermon.

[Roger Caffin]

However, I can work up a full sweat in subfreezing temperatures in minimal base layers and wind protection.
Yup.
Try climbing fast on XC skis with a pack on. It’s good exercise, but we do sweat! See my avatar for an example.

Cheers

[Russ W]

Glad you admit to sweat…beginning to think you might be a reptile!

[Roger Caffin]

Leisure Suit Larry the Lounge Lizard!
And if you recognise that, well … shame.

Do we sweat when going uphill in 40 C heat? Your guess.

Cheers

[Jeffs Eleven]

I have some snow peak pants using octa. I love them for camp pants. My wife loves hers too. I’m not willing to hash out all the detail anymore, but I’m a happy octa user!  I want a hoody of it

[Stumphges]

Jeffs, do you pants have the same kind of Octa – mesh on one face and fleecy stuff on the other face?

[runrig]

I recently purchased the Mountain Hardwear Airmesh 1/4 zip from REI, to use as a lightweight mid-layer over a merino or capilene thermal.

2 things:

1. It is very baggy, and I needed to downsize from medium to small
2. It did not appear that warm at all when walking around under a base layet in even warm temperatures (mid 50s), especially when compared to my Patagonia Thermal.   It is completely porous and the slightest air movement (including walking) goes right through it, which is not a good thing when relying on the trapped air to insulate you.  I need to test it out some more, but it looks like it is not a very useful piece of kit unless worn with a windshirt or rain jacket.

Anyone else tried it out stand-alone in cooler temperatures?

[Matthew S]

Yes, it’s understood with Octa and Alpha 60/90, that they really need a windshell (35+ CFM) over them for them to work. This is actually a good thing, as having two pieces of active insulation just gives you more options for layering.

If you’re a sun hoody user, you’ll probably first donn the windshell, colder still then you go for the octa/alpha. Lots of flexibility.

[Zack Freije]

I have:

• Patagonia R1 pullover M (321g)
• Patagonia Capilene Midweight M (229g)

I was considering Active Mesh or Alpha Direct, but I’m trying to understand what weather conditions in combined with what activity levels are applicable to differentiate these products.

My R1 has historically been my go-to for conditions that I have the potential to sweat, but there is a cool enough air temp or breeze to necessitate a mid layer. It performs excellently, though I tend to prefer it more in the colder temps at the edge of shoulder season or wet/cold/windy.

I haven’t used the Capilene midweight backpacking, but more around town or casual hiking. It does weigh less, so I was trying to decide if that would be a good option for shoulder season or if I should seek out the other two options mentioned previously.

Potentially one key difference is that I don’t typically wear these as base layers. I combine them with another base layer like 150gsm Merino tee or a Patagonia Capilene Cool Lightweight LS tee.

The part I am struggling to wrap my mind around is that my Patagonia Capilene Cool Lightweight LS tee is 3.9oz. The same weight as the AirMesh M crew posted above. The Patagonia shirt feels like nothing. Hard to see pictures of the puffier AirMesh and believe the weight can be the same. I don’t see how this qualifies as a mid layer!

Also, why don’t these brands list weights of their products on the technical specs page? It’s quite frustrating!

[Marcus]

RE air flow – yes, Alpha/Octa offers zero insulation as soon as there is a walking speed breeze (3mph/5kph). Faceless fleece like Alpha is about 40% open space, so any breeze at all will go right through it. Alpha requires a wind breaking layer to be effective at all. This isnt bad though, because Alpha garments are light enough that you can include a 3oz wind shell and still be lighter than faced-fleece garments.

And with the separate wind breaking layer you can adjust the CFM to different activity levels by choosing an appropriate shell, or if used as a mid-layer in a colder setup, you don’t pay the weight penalty of the faced fabric.

But to your point, yes, Alpha garments will offer basically zero insulation with any wind at all unless a wind breaking outer layer is used which is their design intent.

[HkNewman]

Alpha Vs LW Capilene, I could see where the latter is dedicated to being a baselayer.  I’ve seen CDT thru hikers wear the stuff NOBO as a daily short (no UPF, so guessing the back is protected by the pack).   Similarly I’ve heard good things about babying Alpha a bit on cold CDT mornings, but it’s something the hiker felt you wouldn’t want to “push” with it unless under a a shell.

[Zack Freije]

So, in theory, I could use the Alpha instead of the Cap Cool Lightweight as base and throw the Houdini on top for something roughly equivalent to the R1 pullover? It seems a bit hard to believe on the surface. I’d be interested in trying it out to see.

The R1 has really been a workhorse for me that justifies it’s weight and bulk over a range of conditions, but I’m always open to a combination of other layers as replacement.

[Stephen Seeber]

Zack: I think these are two different garments.  The Octa is a wicking layer that happens to have a good warmth to weight ratio.  The Alpha is an insulation layer.  It is hydrophobic.  It does not wick.  I think that distinction makes Alpha more useful as a midlayer and Octa as a base layer. The Octa is slightly warmer than the Cap Midweight, assuming the Cap Midweight I examined is the same as yours.  It might not be, since fabrics change from time to time but the garment name remains the same.  At this point, the Cap Midweight (at least mine) demonstrated better wicking than the Octa. There are several weights of Alpha available.  If you read my article on the search for a fleece replacement, you can get a lot of information on Alpha performance and weights.  I think I would focus a little less on weights of individual layers and more on the conditions you expect to encounter and your level of activity.  As you already know, if your layers are inadequate for the conditions and activity, you are not going to be thinking about the weight you saved, you will be thinking about how miserable you are.

Marcus:  Most clothing characteristics are not black and white (although the clothing could be black or white).  Alpha is a case in point.  I have worn Alpha on many occasions where I want some protection from wind and cool temperatures and judge I still want air penetration to carry off excess heat.  So, I wear the Alpha as an outer layer rather than a wind layer.  The Alpha will stop some wind (my present Alpha is made of 2 layers of 60 gsm alpha and stops a lot more wind than a single layer) and, even in a breeze, provides insulation.  Let’s get more specific.  The air permeability of 60 gsm is so high, I cannot measure it at the standard pressure difference of .5 “/wc.  I can measure it at .04 “/wc.  That is 383 cfm/ft2.  For my 2 layer shirt at .04 “/wc that drops to 72 cfm/ft2 and for a 120gsm, it drops to 55 cfm/ft2. .04 “/wc is equivalent to about 8 mph wind speed.    So, you have choices in blocking wind and insulation levels with Alpha.   So, at times, I find it to be the right solution as an outer layer.  At other times, I might select a wind layer without Alpha, or, if it is too cold or too windy, I will wear both together.  The beauty of layering is that you can select which layers function best at the time.

[Zack Freije]

Stephen,

I thought the Cap Mid and R1 we’re just two weights of essentially grid fleece. With the intent to be a do-all fabric that both wicks and insulates. That’s how I use it.

If the wind starts biting, I add the Houdini which prevents wind from penetrating the fleece, and to some extent, the warmth in the form of water vapor from escaping.

So the question is will either Octa or Alpha provide a similar effect at a lighter weight?

[Stephen Seeber]

Zack: Only you can answer that question. You know what conditions you expect to face.   There is no general right answer that does not consider your activity level and the conditions you are in.   The Alpha does not wick.  Your present base layer does.  So, if you aren’t working up a sweat, the alpha may be fine.  I have worn alpha against my skin and it was fine but I wasn’t sweating much.  If you try it, let us know how it works and describe the conditions under which you are trying it.  The R1 can function nicely as a base or midlayer.  It offers some warmth (not a lot) but it also wicks.  I doubt it will move water vapor as well as alpha.

[Stephen Seeber]

I don’t know what your cap midweight is.  The R1 uses a Polartec bicomponent fabric that is treated to be hydrophilic. It has been called  Power Dry and Power Grid and I don’t know what else during its long life.  I have two Polartec Cap Midweight base layers.  One is a grid.  The other is not.  They might be similar weights.  My Cap Mids are considerably lighter than an R1. They will have lower warmth.   So, as I said above, the fabrics change and the names remain the same.  Octa and Alpha, as I stated, are very different products.  Alpha does not wick.  It has far higher air permeability (depending on fabric weight) than Octa.  I would not replace my Cap Mids with Octa.  I find my Cap Mids wick better and are very close to Octa in warmth.  I don’t own an R1.  I do use other Power Grid heavy weight pieces as base layers in the winter.  I have replaced my use of fleece for a midlayer insulation with Alpha.

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