Stoic VaporShell jacket WPB claims unbelievable

I had a coupon so i was able to get this jacket for about 50$ compared to the 129$ normal. I just ordered it two days ago so as soon as it arrives I will begin some testing to see how it stacks up against event and other materials.

I find the claims to be unbelieveable as well, but even if they are a 1/2 of what is claimed it will still be pretty darn decent,and obviously the higher the better. Until I get the jacket in my hands to test I wont know for sure, will be sure to post a gear review once i get it.

Please do post a review!
What the heck did you do to get that code? I have spent a few grand with them over the years, but 20% off Backcountry gear is all I got!

I won't claim to have an understanding of how these jackets compare in real life environments. In fact where I live a poncho is about all you would need. I did get interested in breathability when I saw your post and found this explanation.
http://backcountrybeacon.com/2010/02/breathability-ratings-windproofing-measuring/

The jist of it is that there is no standardized testing for how breathable a fabric is even though results are often expressed similarly. Manufacturers often use their own version so results between different manufacturers/fabrics are not directly comparable. But, the #s are helpful when comparing different models made by the same manufacturer since they most likley use the same test across the board. This is not the case for for waterproof ratings as those are universal.

Put Put,

I would concede that the published breathability numbers probably come from their own tests (I wouldn't accuse them of fabricating the numbers outright…), but there are standards for testing of WPB fabric breathability.

I recently wrote to someone I consider an expert, and he explained to me that there are six tests that are considered acceptable by the industry. The JIS L1099 B-1 test typically gives the highest numbers, and by this test the highest measured (and published) water vapor permeability value for eVent was 27,826 g/m2 24 hours.

The value of 46,000 g/m2/24 hours published by Backcountry.com indicates to me that they used a nonstandard test, and the only reason a company would do this is to produce inflated numbers.

So, the fact that these numbers may actually have come from a test of some kind doesn't mean Backcountry.com was being honest. They know that most customers are going to just compare these numbers to numbers from standard tests published by other companies and conclude that the Stoic Vaporshell jacket has three times the HH and twice the breathability of the best eVent. This, in my mind, is no different from fabricating the numbers outright. Their intention is still to deceive.

keep in mind, the specs listed for many products on backcountry's site are often incorrect (whether it be their own Stoic line, or other manufacturer's).

The following are quotes from "Ben Wheeler" who responded to a comments on backcountry regarding the vaporshell. He's BC employee according to his profile page.

This initial Vaporshell Jacket was designed as ultralight rain protection – just what you need in a rain shell, nothing you don't. These design calls were made in order to build a rain shell that offers the outstanding waterproof protection and breathability of this Vaporshell Jacket with a great fit while weighing a scant 14oz – all at a price of 129!

As evidenced in this very thread, there are varying opinions on the need to include pit-zips. We chose to err on the side of breathability in this case – in normal conditions, you probably won't ever need them because the fabric is just that breathable. The air permeability of the fabric also aids significantly in cooling and preventing build up of moisture vapor inside the shell. Look for some video uploads demonstrating this incredible waterproofness with air permeability very shortly.

The sleeves were deliberately built a little longer to compensate for a fabric without stretch. Few things we can't stand worse than sleeves that ride half way up your forearm when "down in it."

more specific info on the WPB membrane.

Vaporshell is a Stoic proprietary fabric. Vaporshell contains a PTFE-based membrane – other well known WPF/breathable fabrics also use a PTFE-based membrane. The major difference is the breathability of Vaporshell. Vaporshell also employs a slight amount of air-permeability – i.e. air can pass through the face of the shell, adding further to the venting/breathability of the shell.

The drawback of Vaporshell is that we cannot use our signature welded construction with this fabric – the Vaporshell membrane is not strong enough to hold itself together in a welded seam application. In order to reliably produce this style, we elected to use the traditional cut/sew/tape method long used in the industry.

The vaporshell material performance is incredible. independent testing from SGS has confirmed these numbers with two independent tests.

the mvtr test that is commonly used in the industry is the JIS L1099 B1 method. if companies choose to use a different method, it is generally because a different method results in the fabric looking better, or marketing language. the Vapor shell material can be 4-5 times the breathability of jackets in this price range, and still 2-3 times the breathability of anything else on the market. Mountain hardwear Drique elite, and polartec Neoshell are two comparable fabrics that have recently been introduced in the market.

this is the actual data from Vaporshell materials testing, from SGS testing labs. note this is THE jacket material, not just the laminate.

Water Resistance Test (standard test method ASTM D751:2006 Procedure A; Mullen Method) yields a water column measurement of 68,338.4mm

Water Vapor Transmission test (standard test method JIS L1099 B1 method) yields a measurement of 46,176grams per square meter per 24 hours

This video also shows the functional air permeability of the material while remaining waterproof.

http://youtu.be/tprYmqzV3Kw

While the numbers are impressive, the best way to critique is to try the jacket and test in the real world.

The UPS guy just dropped my jacket off. So I will do a quick initial review.

First Impressions:
I ordered the Black version. I was worried of the bright blue of the zipper in the pictures on backcountry.com, but in person I actually like it. It looks good. Backcountry.com lists the weight as 14.0 oz I weighed it in at 13.88oz. The material for being thin and lightweight has a robust and sturdy feel to it. The material is not too smooth or slippery, it has a rougher feel to it. Seems well constructed and none of the material or zippers seem flimsy or cheap.

Several reviewers and commenters on different sites have complained about the lack of pit zips. I just want to say that this jacket DOES have pit zips. While they are not full length they are ample size for doing their purpose. I didn't measure the exact length of them but they are about 6 inches long or so.

Fit:
I ordered an XL. I am 5'10, and 220lbs with fairly broad shoulders. This jacket has a more athetic cut. So it felt a little tight to me while I was putting it on, but once on I must say that I think it fits remarkably well. So if you have broad shoulders like me this jacket still fits well and provides ample range of motion. I like the extra fabric built into the arms, the jacket doesnt ride and raise up/shift position when moving your arms around. The jacket has a pretty decent length to it, it comes to just below the pocket openings on my jeans. The hood fits snugly on the sides but has ample room for a helmet. The hood is also able to be cinched down tight with two shockcord pulls. The wrists have a velcro tab to adjust the opening.

Performance:
So I have worn the jacket for about two hours so far. Its about 70-75 here today with a mild breeze. Walking around my house for about 30 minutes feeling out the jacket I was very comfy and didn't seem warm. If you move with any force or turn quickly you can actually feel a little air come through the material. I went for about a mile walk in my neighborhood and remained comfortable the entire time, I ran back the last half mile or so and started to work up a light sweat. I could feel the jacket breathing, and when running or when a strong breeze came by you could feel a little airflow come through the fabric, Not much but just enough to be noticeable. When I got back home I did some jumping jacks etc for a few minutes to warm up and start sweating a little. I can say without a doubt this jacket breaths pretty good from first impressions. I hope to get out for a dayhike thursday or friday to give it some more tests. Supposed to have rain sat and sunday also, so testing will be on going.

I stood in the shower for about 10 minutes, and the fabric did not wet out in any spots, and the dwr performed well with water beading and rolling off. I allowed the water to hit on all the zippers for a minute or so. Chest pocket zipper and main zipper have a good seal. Holding my arms up and leting the water hit the pit zips there is very minor leakage where the two zippers on the pitzip meet. So unless you walk around in rain storms with your hands over your head for minutes at a time i don't really think this is an issue.

Will post some updates after a few hikes. But initial impressions are I like the Stoic Vaprshell.

Does air pass directly through the fabric when doing the fabric to mouth breathing test? That is, can you suck air through it? You can draw some air through eVent in this fashion, but not Gore-Tex and most (all?) PU membrane WPB fabrics. Thanks!

Yes, you can suck air through the fabric. It's not alot, but some. I have never done this with event so i have nothing to compare it to in that regards.

I have been able to to take the jacket out for about 5 or 6 hikes now this past week, and luckily it has been raining almost non stop. So far so good. Seems waterproof enough for me and did not seem to wet out anywhere despite being in constant rain for 3-4 hour stents. It also breathes very well. The temps this past week have been around 60-70 on average, and kinda muggy and humid when not raining. Two of the hikes were in a steady hard downpour and the jacket performed flawlessly, the others were in light rain and drizzle/mist conditions. I was able to keep a happy equilibrium while hiking and did not over heat to a great extent. I was sweating inside the jacket as was expected(I kept the jacket zipped up all the way the entire time hiking to really judge it's breathability), but the jacket does a very good job of breathing and I felt comfortable the entire time. It was a noticeable difference from many other rain shells I have tried. I am very happy with my purchase thus far.

I can't get beyond what I feel was a deliberate attempt to tout a set of numbers that were unbelievable to begin with, especially in light of the fact that they were confirmed and staunchly upheld repeatedly during the course of so many inquiries as to their credibility. BC knows the difference in their testing procedures, and that the industry standard is the static water column test. Bill Hartlieb's correction on the BC site product page (but not here for some reason) is appreciated and deserved, but I'm left with the feeling that it was little more than a case of damage control after having been caught. An apology and an explanation is due. The difference between 68k mm and 28k mm is the difference between a miracle material that takes waterproofness to a whole new level, and a mediocre jacket/fabric that will now have to live or die based on its own merits. Certainly the numbers are still admirably high, especially given the low price point, but when it comes to my gear, price is much less one of my criteria than is performance. I expect to pay a premium for equipment that I trust my life to and I have to rely on accurate and honest evaluation to get me there. Toying with that for the sake of marketing is almost unforgivable…you're willing to potentially risk my life for the sake of pushing product??? Absolutely shameful, and not at all what I would have expected from Backcountry, ever!

Phil, I agree with you that BC should have known better, but let's not get carried away. First of all, a 28k mm HH is way, way more than anyone would ever need of a rain jacket. Unless you're going up against a fire hose between 10k and 20k mm HH is more than enough to keep you 100% dry.

Secondly, the 68k claim is just so unbelievable, and 28k is such a respectable number already, that I find it hard to believe that anyone at Backcountry could be stupid enough to believe that it would fool the market for any amount of time. I can understand trying to tweak numbers if their Vaporshell was testing at like 5k HH, well below the industry standard for "waterproof", but exaggerating numbers when the real number is so high? Just doesn't make sense.

I have no question about the waterproofness of the Vaporshell, however I do have questions about the breathability of the stuff. Waterproofness and breathability are related in that a porous membrane must have holes large enough to allow water vapor to escape but small enough to prevent liquid water from entering. The more waterproof a material, the less breathable it can be. This is inescapable.

Polartech have limited the waterproofness of their NeoShell membrane to 10k mm HH in order to maximise its breathability while still being able to claim it as "waterproof". They could increase the waterproofness of the microporous PU membrane by simply making the pores smaller, but this would reduce its breathability. eVent is an example of a waterproof microporous membrane that is far more waterproof at the cost of reduced breathability.

My question is: how have Stoic managed to overcome this inverse relationship between waterproofness and breathability?

The relationship isn't that simple. eVent and Gore-Tex Pro Shell are both more breathable and more waterproof than many other WPB fabrics. Looking at a wide variety of other WPB fabrics, the idea of a simple inverse relationship isn't evidenced. More often than not, there is a direct relationship between MVTR and HH; e.g. 10K/10K for Marmot Precip and 20K/20K for Marmot Membrain. There may be exceptions, but this is a distinct pattern.

"than hasn't other fabrics" What?

Those figures are not only purely anecdotal but the two numbers (xxk/xxk) you relate are for entirely different units of measurement. One measures hydrostatic head in millimetres and the other measures grams of water transport per metre squared per 24 hrs. They are totally incomparable and more useful for marketing than for actually determining the real-world characteristics of a fabric.

In a microporous fabric, there MUST be a relationship between the water resistance and water-vapor permeability. The bigger the pores, the better the breathability and the poorer the water resistance. It's (simple) physics, it's (obvious) logic.

Edit: Also something I haven't mentioned so far in this thread is that the industry standard breathability tests are extremely suspect. The "inverted cup" test that most manufacturers use to come up with ratings like "20k g/m^2/24hrs" doesn't take into account relative humidity, temperature or pressure gradients across the samples and yields whacky results like rating a WPB membrane higher on the breathability scale than a 200 weight fleece, which of course is not the case in the real world. The only thing you can take from numbers which were acquired using that test is how well they perform in that test.

A far better method is the US Army's DMPC, which you can read about here:
http://www.ssc.army.mil/about/pao/pubs/warrior/97/aug/breathe.htm

And which yielded this comparison graph for waterproof fabrics.
http://www.verber.com/mark/outdoors/gear/breathability.pdf

Bottom line: There are no "magic" materials, every membrane/fabric must obey the laws of physics. Reason says you can't increase waterproofness without limiting breathability to some extent. So how is Vaporshell achieving such high waterproofness without sacrificing breathability?

Hi Jeremy,
Yes, I reread my post, and it did get a little carried away. I apologize. However, what I was trying to emphasize is that there are always consequences to actions, be that an oversight, or whatever. If it was ever a question of BC's well-being over those of any end user, I find that unacceptable.

I was one of the original posters on the Vapor product page. Simon Hatfield raised a question about the numbers being so high. Immediately, flags went up, and a number of phone calls/chats ensued. We were all adamantly assured that the numbers were correct. Whether the "gear gurus" knew about the testing discrepancies is doubtful, but still, the numbers were presented in the specs using a standard format for static HH testing. With the exception of their staggeringly high values, nothing would have given a potential buyer any indication that they were anything but the product of a measure used, not only by other manufacturers, but in the procedures used by BC itself on every other piece of non-proprietary gear whose performance they confirm for themselves. BC knows that Stoic data is hard to come by, except that which they present on their own behalf. Since then, independent tests have been conducted, but it still doesn't answer the question of why there was any deviation from a common practice and a uniform testing standard initially. It would seem that only two possible scenarios could be at play- 1) somebody screwed up and had no idea what they were doing 2)there was an intention to mislead.

I agree that the updated results on the testing of the fabric itself is impressive (although 30k mm is my usual benchmark), but as many people are pointing out in their reviews and non-scientific tests, the jacket as a whole has some discrepancies in its overall performance and design.

For my purposes, I'll take the "real-world" experiences of my peers any day, and quite frankly, I'm finding that at this time, based on their reviews, I have no use for the Vapor. Mere oversights in specs and data is completely understandable, but I just feel that this went beyond that level , and I would like to know the truth as to why.

@Ken s/hasn't/many – replying from phone. :)

@Jeremy
I understand that HH and MVTR measure different properties. Indeed, that's how it needs to be if we are going to infer anything from any sort of relationship between the values.

In microporous fabric, there needn't be a relationship between water resistance and water-vapor permeability unless you're talking about tweaks to the same fabric. With a given technology, that's true- your example of NeoShell is apt. However, this cannot be extended as a general rule across all WPB fabrics.

If this were true, Marmot Precip would be more breathable than eVent and Gore-Tex Pro Shell. Let's refer to the numbers:

Fabric HH MVTR
eVent 30,000 22,000
GTX Pro Shell 28,000 25,000
Marmot MemBrain 20,000 25,000
Marmot PreCip 15,000 12,000

Precip has a HH rating of 10-15K, while eVent and Pro Shell are 30K and 28K respectively. If there is an inverse relationship between waterproofness and breathability, we would expect the MVTR ("breathability") of Marmot to be higher than both eVent and Pro Shell.

I admit, your hypothesis makes an intuitive kind of sense- but the data doesn't support it. If you're going to invoke the laws of physics, you need to back it up with data. If you deny the validity of the ratings, perhaps an appeal to anecdote would suffice? Wear a Marmot Precip and take a walk around the block. Do the same with an eVent jacket. Are you seriously going to claim that the Marmot Precip breathes a lot better?

Let's look at the US Army's DMPC values. Since Dr. Gibson makes no comparison between the DMPC rating and hydrostatic head of the tested fabrics, we have to rely on the HH numbers we have from other sources are compare those with the DMPC values. Since a lot of the fabrics tested aren't really made, I'm going to focus on eVent, GTX, and Membrain.

The first graph, with Water Vapor Diffusion Resistance (s/m) (Lower Resistance is More "Breathable") on the Y-axis, shows these fabrics as the most breathable. I'll list HH along with this. For the fabrics we can use for comparison, Dr. Gibson's testing found that eVent was the most breathable, followed by GTX XCR, GTX Standard, and Marmot Membrain. If there was an inverse relationship between waterproofness and DMPC, we should expect to see the numbers going up down this list not down.

Fabric – HH

EVENT Laminate – 30,000
Gore-Tex XCR – 30,000
Gore-Tex Std – 28,000
Marmot Membrain – 20,000

I can't find any good HH ratings on the older Gore-Tex- feel free to jump in if you can find any. I used the best data I could find, mostly on older product pages. I'm trying to avoid selection bias as well as I can, but since he doesn't provide actual numbers for the DMPC tests it's nearly impossible for me to take this data and toss it up on a graph showing DMPC vs hydrostatic head.

I agree that the industry standard MVTR rating is not perfect. Even so, the DMPC values do not point to there being an inverse relationship between waterproofness and breathability. To some extent, all breathability ratings are worthless- in the 100% humidity of a wetted out face fabric, a fabric isn't going to breathe whether it's eVent or Precip.

You may be misunderstanding me. I'm not arguing that there is such a thing as a "magic" material. I'm also not stating that there is a magical, universal direct relationship between waterproofness and breathability.

I suspect that the relationship between waterproofness and breathability involves more than simply how large the pores are when we're discussing WPB fabrics. There are other users here better qualified to speak to how this is done.

Reason says that, contrary to intuition, you can increase waterproofness without limiting breathability, and that it is often the case. I don't pretend to understand the how and why, but since the preponderance of data points to that being the case I don't think there is any other conclusion one could come to rationally.

Aaron, my point is not that there is or should be an inverse relationship between waterproofness *ratings* and breathability *ratings* , it is that in a microporous material there should be (and is) an inverse relationship between *actual* waterproofness, which is amply demonstrated by the standard hydrostatic head test and the *actual* breathability, the best test of which is, I believe, the DMPC. The standard test for MVTR, the inverted cup test, is basically worthless and thus any MVTR data gleaned from it is, I believe, meaningless in the context of this debate.

Another reason WPB materials may not display the expected relationship between waterproofness and breathability is because most of these materials (with the notable exceptions of Vaporshell, eVent and NeoShell) use some sort of monolithic, (air impermeable)coating to protect their ePTFE membranes from contaminants. The original Gore-Tex membrane was super breathable and waterproof but was susceptible to damage from the oils in skin. To fix this they somewhat sneakily added another monolithic oleophobic coating to their ePTFE membrane, rendering it oil-proof but also severely reducing its breathability by removing the mechanism of water vapor transfer by convection. Nowadays Gore-Tex and most other WBP fabrics "breathe" through diffusion, not convection. That is, the air impermeable PU layer must absorb the water vapor rather than allowing it to pass directly through it. The reason eVent breathes better than Gore-Tex is exactly because they managed to protect their ePFTE membrane without resorting to a monolithic oleophobic coating: their method allows the ePFTE pores to remain open and thus allows water vapor transmission via convection, or "direct venting" as eVent calls it.

In a fabric that uses a monolithic structure, the relationship between waterproofness and breathability may not apply because the primary process which *limits* the breathability of such a fabric breathes is not directly related to how it repels water. Water is prevented from entering the fabric by the outer ePTFE membrane, but water vapor transmission is limited by the diffusive capacity of the PU layer. Only *after* the water has diffused through the PU player does the ePFTE membrane come into play, and usually (read: always) the diffusive permeability of the PU layer is far less than the convective permeability of the ePTFE membrane. The PU player is the "bottleneck" for breathability in fabrics which use it.

In fabrics which do not use a monolithic layer, and which therefore have open pores that allow "direct venting", such as eVent, NeoShell, Powershield Pro and I assume Vaporshell, the expected inverse relationship between waterproofness and breathability characteristic of *microporous membranes* should be evident. Indeed it is: eVent is more waterproof and less breathable than NeoShell or Powershield Pro and Powershield Pro is less waterproof but more breathable than the others. This brings us back to my original question of how Vaporshell is able to supposedly outperform NeoShell in terms of breathability and eVent in terms of waterproofness. I just do not see how it's possible and suspect that it merely performs well in the "inverted cup" tests and would not perform nearly as well in the DMPC or in the real world.

I realize it's rather late, but I would like to point out an obvious flaw in the logic that "higher breathability means less waterproofing." What you are not taking into account is the strength of the membrane. The hydrostatic head test gives the value for how much water pressure can be applied to a membrane before water leaks through. Water leaks through because the high pressure forces the holes in the membrane to expand, or rupture. This can be prevented by using materials for the membrane with a higher tensile strength than is average, or in the case of Gore-Tex, protecting the membrane with a polyurethane coating that also adds strength to the membrane. ePTFE is a material that can be manipulated in many ways, and all Stoic had to do was use a thicker than usual membrane with larger than usual holes, and they get a higher tensile strength, which keeps the membrane from rupturing, while allowing for more breathability.

For what it's worth, I own a vaporshell, and I love it. It really is incredibly breathable, and rivals my North Face Kishtwar with Powershield Pro for breathability. I know there is a difference in face fabrics, but even so, it's quite impressive. Phil, 28K waterproofing is so far beyond what you need that it's ridiculous. 10K is the industry standard for fully waterproof (even under pressure from knees, elbows, etc.), and anything above doesn't really serve much of a purpose. Think about it, if you've been diving before, the pressure at 30m or so down (100 feet) is very high, and that's the kind of pressure your jacket can deal with before letting in water. You will never experience a situation like that in real life. The numbers are higher than they need to be in order to look good.

I don't know whether or not BC screwed up with the 68K thing, but I ordered the jacket the day it came out anyway, and whatever the HH is, the jacket has kept me dry and comfortable multiple times, and I prefer it to it's three-times-more-expensive cousin, the Stoic eVent Stash shell.

Hope this can clear up some dispute.
Cheers.

Is the Vaporshell jacket even made anymore? I don't see the mens on the backcountry site, and the women's is on clearance.