- Jan 8, 2019 at 2:52 pm #3572126
Jeff HollisBPL Member
I hope this new technology from TNF and it’s partner live up to it’s claim. If so it would up end the waterproof/breathable discussion.
JeffJan 8, 2019 at 3:59 pm #3572135
John HBPL Member
@johnnyh88Locale: The SouthWest
It does sound like it would make a nice rain jacket fabric. I wonder what the weights and cost will be? Maybe some new WPB bivy designs?
From the article:
The moisture vapor transmission rate (MVTR) is 75,000 g/m²/day. For context, the highly breathable eVent fabric has a top MVTR of 30,000 g/m²/day. That means a lot of water vapor can move through FUTURELIGHT products quickly. It also allows air to move through it quickly, at a rate of about 1.5 ft³/minute.
1.5 CFM would be very breathable for a rain jacket, but I can still overwhelm windshirts with a 10 CFM rating. Add in some pit zips though, and that might convince me to leave my windshirt at home.Jan 8, 2019 at 11:57 pm #3572181
STEPHEN SBPL Member
We’ll see. We seem to be in an MVTR arms race. The highest claim I have seen is Porelle Extreme, which claims 120000 g/m2/24hours. That is the equivalent of 11 lbs of water per hour or 1.375 gallons of water per hour/meter square of fabric. It is difficult to envision that much water vapor diffusing through a membrane. What is most important is to determine what test is done to come up with this number and what vapor pressure differences are used to obtain such results. Most manufacturer’s don’t reveal their testing method or the test conditions. As a result, we have no little idea how the garment will perform in real life. Especially since membrane performance can vary according to temperature and humidity conditions. Like John H, I will overwhelm any water proof/breathable membrane I have tried during periods of high effort. If these things show up with pit zips, I guess we will have our answer.Jan 10, 2019 at 3:19 am #3572479
Eric BlumensaadtBPL Member
@danepackerLocale: Mojave Desert
Better than eVent? If so the uses will be many:
- single wall tents (no need for an inner wall)
- shells for seam welded down and synthetic puffy clothing
- sleeping bag shells
- WPB liners for shoes and boots
BUT… will it be more expensive than Gore-Tex Pro Shell?
BTW, why is it I see fewer eVent clothes than before? I like my eVent rain suit.Jan 10, 2019 at 2:18 pm #3572536
Brad RogersBPL Member
@mocs123Locale: Southeast Tennessee
1.) Gore Tex has pushed eVent out of the market. Montane REI and Mountain Hardwear have moved from eVent to GTX Gore will not let you sell there products if you also sell eVent
2.) Some of the newer GTX fabrics (Pro Shell? Active?) have caught up with eVent.
3.) GE (who owns eVent) is in financial trouble.
4.) Possible durability issues??? 2 of the 3 eVent products I own delaminated. One, an REI jacket used around town is still ok.Jan 10, 2019 at 3:28 pm #3572546
John S.BPL Member
Tha seems monopolistic of Gore?Jan 10, 2019 at 5:34 pm #3572551
Dan DurstonBPL Member
I’m not optimistic there’s much value here even if the claims are true.
If it’s not raining, this membrane is still way behind a windshirt. It’s 1.5 CFM whereas my favourite windshirts are about 50 CFM. So this isn’t going to feel anything like a good windshirt.
If it’s is raining, then the humidity outside is almost certainly 100% and very little moisture transport will be possible regardless of how good the breathability is because you need a humidity differential for breathing to occur (yeah body heat helps a bit but not much). So it’ll still feel like any other rain jacket in the rain. By far the most important thing in the rain is that the material is reliably waterproof, since all the breathing in the world isn’t going to overcome even a little leaking. So at best it’s like a rain jacket + bad windshirt.
I think pursuing ever higher breathability in waterproof gear is largely a misguided adventure. Too often these garments sacrifice quality waterproofness in the rain, just to do a poor job of replicating what a 2oz windshirt can do when it’s not raining. Very little potential gain over a rain jacket + 2oz windshirt combo. IMO, it’s better to have something solidly waterproof. It doesn’t sound like this stuff is really that waterproof because they aren’t making very clear claims there, but even if it is, I think the overall improvement would just be marginal. Perhaps a small advantage on rainy trips where it stops raining every now and then so you can dry out a bit, but don’t want to bother switching to a windshirt.
I guess I’ve just been burned too many times – every time someone comes out claiming breakthroughs in breathability it ends up that it’s not waterproof enough and then there I am in the rain, soaking wet in the “most breathable” jacket because it can’t also keep rain out after a few uses.Jan 10, 2019 at 7:50 pm #3572579
Edward John MBPL Member
To add to Dans pertinent comments such UL fabrics are not really stormproof either as the fabrics are simply not stiff enough to counter wind pressure. Although weathering such conditions isn’t usually what UL gear is good at/ designed for it happens sometimes that people find themselves in such circumstancesJan 11, 2019 at 11:38 am #3572677
Woubeir (from Europe)BPL Member
If it’s is raining, then the humidity outside is almost certainly 100%
Instead of explaining it myself, read this: https://boards.straightdope.com/sdmb/archive/index.php/t-257644.htmlJan 11, 2019 at 3:28 pm #3572686
Well even 90% is humid enough.Jan 11, 2019 at 3:59 pm #3572691
Dan DurstonBPL Member
Interesting read. I stand corrected on my statement that rain equates 100% humidity at ground level. As Ken said though, even if it is 90 – 97% that’s still not much of a capacity to take on additional moisture. And you would need a solidly functioning DWR to realize even that because a failed DWR means a soaked outer nylon layer which would be at 100% humidity.Jan 11, 2019 at 10:09 pm #3572748
Dan MaddenBPL Member
Often confused with air permeability, breathability is by far the most misunderstood term in the outdoor industry… while the two are similar, they are completely different in function. Air permeability is the passage of air (most often wind) from the outside of a garment to the inside and is measured in Cubic Feet per Minute (CFM). Breathability is the movement of moisture vapor from the skin to the outside, often through multiple layers of clothing. The confusion arises from how breathability is measured. The only reliable way to measure breathability is the Sweating Hot Plate which measures resistance of a barrier to the transport of moisture vapor to the outside, i.e., the higher the resistance, the lower the breathability of a barrier is said to be, be it a t-shirt or shell garment. This test is accepted globally by leading labs such as Natick, Hohenstein Institute, Kansas State, etc. The main reason it is so widely accepted is that the data correlates well with human subject testing because unlike MVTR data, the resistance doesn’t doesn’t change with climatic conditions, plus the numbers are cumulative (read: layers). MVTR test data is simply lab data used by fabric manufacturers as an internal quality control test. For the sake of consistency, these tests are performed under tightly controlled environmental conditions. The main issues with MVTR numbers are: 1) there at least 10 different MVTR test, e.g., inverted cup, upright cup, etc., with each test giving widely different results – a real bonus to the marketing department since they can use the ‘best’ test numbers to make their products look great; and 2) if you change the lab conditions, then guess what? the MVTR data also changes which in turn means it has no correlation to human subject testing since we all live in a constantly changing environment.
The other issue with understanding breathability is that machines don’t wear garments, people do – and each person has a different perception of what ‘comfort’ feels like. This, coupled with unrealistic expectations, creates the world of ‘my garment doesn’t breathe’. The real issue however, is that most garments actually do ‘breathe’, albeit at different rates, but not nearly fast enough to handle the moisture vapor that your skin is producing under strenuous conditions – in fact, a wicking t-shirt can’t handle most of the moisture vapor the skin produces during strenuous activities… so why would you expect a waterproof/breathable shell to be some sort of ‘air conditioned, climate controlled’ garment?
The key to breathability is the strength of the ‘driving force’ within a garment, i.e., high heat/humidity seeks to equalize itself with low heat/humidity. If this doesn’t or can’t take place, then breathability doesn’t occur – but it’s always nice to be able to blame something other than the laws of physics. As an example, if you are skiing at Jackson Hole and the ambient temperature is 25 degrees F and your skin temperature is 94 degrees F, then you have a strong driving force (assuming you haven’t overdressed). Conversely, if you are hiking the AT in mid-July and the ambient temperature is 90 degrees F and your skin temperature is 96 degrees F, then there is no driving force – especially if it is raining since humidity levels are very high – in this case, an umbrella is highly recommended.
So what does all of this have to do with FUTURELIGHT? Very simply… MVTR numbers, etc., really mean nothing except they are a huge bonus for the marketing dept. As noted before, machines don’t wear garments, people do and at the end of the day, the proof will be in wearing these garments and how they meet your expectations. It’s also important to remember that the ‘testers’ are paid TNF athletes and/or received the garment for free…so what would expect them to say?Jan 11, 2019 at 10:51 pm #3572755
Greg MihalikBPL Member
MVTR – Moisture Vapor Transfer Rate
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