A NEW PARADIGM FOR UNDERSTANDING WPB FABRICS

[Richard Nisley]

This is the first WPB to be tested using “A New Paradigm for Understanding WPB Fabrics”. The next post will provide the test details.

[Richard Nisley]

My test details are in pdf format on my Web site  Here

Please provide suggestions for making my Web site’s detailed pdf test report a more refined and useful tool.

The executive summary follows:

The Columbia Sportswear Outdry EX Featherweight is advertised as having an 8 oz weight in medium. The item I tested was a Cobalt Blue model in size XL that weighed 7.83 oz. The MVTR measured higher than eVent or Paclite versions that I compared to it. Its durability is adequate for backpacking including bushwhacking.

Their web site is incorrect in that it states there are pit zips. The venting zips are large vertical pocket / vent combinations that end above a backpack waist belt. The pockets are backed by mesh and are large enough to use as a stuff sack, carry a large map, or dry gloves. They are identical in position and size to what Natick is now using on their highly tested Level 6 rain gear. The picture on the Web site is also partially incorrect because it doesn’t show the Velcro wrist straps that allow a wide range of tightness.

The hood has two sets of adjustments for a great storm fit. The material is supple and comfortable to wear. There is no bungee at the waist but that is OK with me. The bottom flares out slightly to keep your pants dry down to your crotch. My backpack belt seals the bottom if that is what I need. The garment is cut for layering and has great shoulder mobility for guys with athletic upper bodies.Aesthetically it drapes much nicer than the heavier material Outdry EX Gold model that I also tested.

[Michael Gillenwater]

it would be super helpful if the axes on the graphs were separately labeled with titles and units

[Richard Nisley]

Michael,

Done

[Diane Pinkers]

I’m interested in your tests at 32F with a 1.2 mm fleece layer. Not conversant with the options in the market, could you give me a commercial example of a garment made of similar fabric? Patagonia Cap 4?

[Richard Nisley]

Dianne,

I tested using a Polartec fleece with an areal density of 150 gm2.

This was a static test and  Polartec150 was the lightest insulation that would result in an acceptable skin temperature at my test’s 1.5 MET rate.

For an environment with a 7 MET (backpacking in mountains) activity rate at 32F with heavy rain, I would have used a similar weight insulation but in Powerdry construction for better sweat movement away from my skin. Either a Cap 4 (aka expedition weight), R1, or equivalent material from another vendor would be ideal.

 

[Paul S]

Richard,

How are the watts calculated per MET unit? I found the conversion formula. They (still) seem very high to me intuitively, but… no wonder I’m always starving. Thanks for the great read.

 

 

[Tad Englund]

Richard, great report as always.
I just read your report and could this be a game changer in for the industry or just another option?

[Richard Nisley]

Paul,

Great question; I also had it and this is what I did to answer it for myself.

Step 1 : I researched the watts numbers in a $232 book called “Intelligent Textiles and Clothing”. I thought their watt numbers were too high.

Step 2 : I converted their watts numbers to METs using these calculations:
A) Multiply Watts by 0.0143 to get kcal/min
B) Divide kcal/min by 5.05 to get liters of O2/min
C) Divide liters of O2/min by bodyweight in kg (pounds ÷ 2.2) to get mL/kg/min
D) Divide mL O2/kg/min by 3.5 to get METs

Step 3: I then verified my calculated backpacking MET value against The Compendium of Physical Activities Tracking Guide (gold standard for physiology research). It shows:

 

[Thomas Sabido]

I guess I’m more like a Special Forces guy, as the technical details are way above my pay grade. Thanks for the work (evidence), the technical expertise, and the summary (quoted below)

Can you give examples (different brands) of the bicomponent wicking baselayer / Level 5 softshell/ Level 4 windshirt?

”if it is raining and you are active, wear a bicomponent wicking base layer (Power Dry) in combination with either a level 5 softshell (5 CFM and >300 mm HH) or a Level 4 windshirt (25 CFM and >300 mm HH)”. You will be more comfortable and efficient than with any WPB. “If you are static, wear a WPB shell.” My aforementioned list of watts or METs, for different activities, provides more refined guidance as to “static” not being a point but a range.

[Michael Gillenwater]

Thank you Richard (on the graph labeling)!

[Richard Nisley]

Tad,

Game changer for the industry… no, not for front-country use or just a weekend in the back-country.

Game changer for the industry… no, not for rainy weather back-country conditions longer than a weekend by low-information consumers.

Game changer for the industry… yes, but only for rainy weather back-country conditions longer than a weekend by high-information consumers (small fraction of the total market).

[Michael Gillenwater]

Game changer for the industry….I have no idea, as all my info comes from what I see here and on the web.

….but being based in the Pacific NW, the thought of having a 6-7oz rain jacket that does not wet out and sacrifices nothing on the (small) benefits of a vapor permeable membrane is pretty appealing.

[Richard Nisley]

Thomas,

You said, “Can you give examples (different brands) of the bicomponent wicking baselayer / Level 5 softshell/ Level 4 windshirt?

Military L2 bi-component wicking base layers: UL commercial equivalents Web Search

Military L4 or L5 equivalent UL commercial equivalents:

Similar to L4 CFM and HH specs: Montbell UL Stretch Wind Parka, XL = 4.6 oz, HH = 482, CFM = 17.6 (normally a March/April restock)

Similar to L5 CFM and HH specs: Patagonia Houdini, XL = 4.1 oz, HH = 387, CFM = 3.7

Note that although both of these commercial items have adequate HH performance, their DWR is C6 versus Epic for the military versions. They will have a colder surface temperature after the DWR wears off but the bellows action from hiking will keep the larger, than WPB, pores open for breathability.

Also note that their CFM values are lower than the equivalent military versions.

 

 

 

[Jarred O]

Richard,

As always, thank you for sharing your work with us. I, as with others, continue to reference your work and disseminate it as one of the best points of departure for data driven considerations of clothing systems.

One question I have which perhaps you know the answer to:

Is the Wild Things windshirt still the only readily available offering with an Epic fabric which conforms to >25 CFM/>300 HH requirements? (I inquired to WT in January of 2017 and it was still the same fabric). Having spent a considerable amount of time looking through the military offerings on both eBay and private sellers online I have not been able to find a windshirt with known values. The WT windshirt continues to suffer from an odd, somewhat boxy fit.

If I recall from previous readings you switch between two military epic windshirts given the conditions. The peices you have are known CFM and HH values because of your own testing and are either no longer readily available online or have values which are not able to be known by inquiry.

[Tom Beno]

This is good stuff, Richard, thank you. As Michael posted a short while ago, this could be just the thing for extended trips in the PNW. Olympic and Mt. Rainier will wet-out just about anything in short order.

[Richard Nisley]

Jarred,

You said, “Is the Wild Things windshirt still the only readily available offering with an Epic fabric which conforms to >25 CFM/>300 HH requirements?”

My WT 1.0 in the color multicam, 2013 version, tests 29.8 CFM, 281 mm HH, with Epic DWR,70 denier high tenacity nylon 6,6, and 9.4 oz in XL.

My WT 1.0 in the color multicam, 2014 version, tests 32.6 CFM, 351.5 mm HH, with Epic DWR,70 denier high tenacity nylon 6,6, and 9.4 oz in XL.

My Patagonia PCU L 3A (Alpha active insulation) in the color multicam, 2016 version, tests 34 CFM, 315.4 mm HH, with Epic DWR 70 denier high tenacity nylon 6,6, and 18.5 oz in XL.

The WT 1.0 coyote color (2013 and 2014) fabrics tested 2.7 CFM and 421.8 mm HH.

I have bushwhack hunted with my 2013 WT 1.0 for 4 years and have yet to get a tear or have the DWR diminish.

When I am not going to be aerobic and want to be stealthy, fly fishing as an example, I wear my very old ORC block 0 PCU L4  in the color alpha, 2010 version, tests 3.6 CFM, 492.1 mm HH, with Epic DWR, 70 denier high tenacity nylon 6,6, and 11.5 oz in XL.

None of the above garments are ideal for UL backpacking (too heavy) or wearing around town (too ugly).

Up through 2013, the Arcteryx Squamish was manufactured with 35.5 CFM and 300 mm HH but they achieved that with a clear PU coat on the back side. It washed out after a few times and dropped down to just the fabric weave providing the barrier at 70 mm.

 

[Richard Nisley]

All Posters,

Thank you for the positive feed back.

[Brad Rogers]

Thank you for all of your work Richard, I very much appreciate your contributions to BPL. I think this is potentially a game changing shell (or at least technology), particularly if it proves breathable and durable. How does the material feel against the skin? Is it more like a 3 layer GTX or eVent shell or is it clammy like most 2.5 PU shells or Packlite? It sounds like you like the hood, wrist closure, and overall fit, so that is good to hear. I would love to see a version of this shell with pit zips instead of the pockets (and perhaps a lighter color).

I wonder if Columbia owned Mountain Hardware will sell jackets with this technology.

[Richard Nisley]

Brad,

The inner jacket is lined with a polyester fabric treated to be hydrophillic. It feels similar to conventional 3L WPB jackets from other manufacturers.

 

The heavier Outdry EX stretch is offered in a “Gravel” color in addition to the same black or blue currently offered for the EX Featherweight.

 

[Woubeir (from Europe)]

Richard,

could you get your hands on a GTX Active with Shakedry-jacket ? As I wonder how it scores in your test and if they also can make it more durable to roll out the technology to other ranges.

[Richard Nisley]

Woubeir,

The Gore Shakedry jacket manufactures all say that their products, built using the current material version(s), are not warrantied to wear under a backpack. When a Shakedry product is offered without that warranty restriction, I will test it .

 

[Eric Blumensaadt]

Richard,

To give us an example:

Using your new criteria v.s. the older criteria (side-by-side graphs?) would “standard” eVent and Gore-Tex Pro Shell give similar breathability and exterior water resistance figures? (I did not say HH because you feel it is not an entirely valid test for WPB active wear.

If not what would account for differences in performance?

[Richard Nisley]

Eric,

Yes, standard eVent and Gore-Tex Pro should provide similar breathability for both test cases.

 

[Woubeir (from Europe)]

Richard,

once you test Gore Shakedry, could you test the CFM also (here you didn’t because it was irrelevant as Outdry Extreme has a CFM of 0) ? Because I’m curious how the combined effect of MVTR and air-permeabity affects the overall breathability. E.g. hypothetically, between Outdry Ex  and Gore Shakedry, Outdry Ex might be the best regarding MVTR, but the fact that the product from Gore is air permeable could give it overall the better breathability.

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