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nian zhang
(thotwielder) - F
how breathable a wind shell is on 11/26/2012 10:40:09 MST Print View

Hi all,

I saw so many people here praising their wind shells. Just wondering how breathable they are compared to latest hard shell like Gore active shell, event or dry Q. Like 10%, 20%, 50%? I am thinking if wind shells only offer a little bit (around 10%) of more breathability then I probably will not get one.

In fact I already got a Montane pertex wind shell. I used it several times but it seems there was not too much difference with my event shell. I meant when I work hard I sweat anyway. Or when it's not that windy or even sunny I probably will just hike in my base layer. And in winter or cold days I have no problem wearing my event shell all day with only my base layer or a synthetic jacket/vest (I have both). And since my synthetic jacket is wind proof, I sometimes just wear it without a shell. Moreover a hardshell provides much more breathability when the underarm zip is open. So I ended up using the wind shell only for cycling in cold days because it's guaranteed to have lots of wind chill and it's more slim than my event shell. At this point I'd ask is wind shell really necessary when you have to bring a hard shell anyway because I will bring a hard shell anyway since I am the type of always preparing for the worst. And my hard shell is sub 300 g (westcomb specter lt), it's really not a huge difference in terms of weight with most wind shells.


But I saw so many people praising their wind shells about breathability etc, I began to wonder are their wind shells much more breathable then my Montane pertex? If yes, does it mean it's at the cost of windproofness? If there is a windshell providing 'significant' breathability then my event shell and still is wind proof or very much wind resistent then please enlighten me.

NZ

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: how breathable a wind shell is on 11/26/2012 13:08:41 MST Print View

Nian,

A hard shell made with a porous membrane, such as eVent, provides “worst case rain protection” in combination with air permeability as high as .53 CFM. This is what I measured on the Integral Designs Thru Hiker. I measured the air permeability of the Rab Boreas windshirt, which Dave C. gave the highest rating in his recent SOTM report; at 68.69 CFM but with no external moisture protection. THE DIFFERENCE is 68.69 / .53 = 1,296%.

To put the windshirt air permeability spectrum in perspective, the most breathable windshirt I have measured is the Acteryx Squamish at 100.59 CFM. The windshirt that will achieve the optimal balance point, for most people while UL backpacking, is the Houdini.

I measured the older Pertex Classic fabric and it was 3 CFM. Assuming this is the Pertex fabric used in your windshirt, it is a very poor choice for use while UL backpacking. I also measured the North Face Verto windshirt using the newest Pertex GL fabric and it was even worse at .53 CFM, the same as the Thru Hiker eVent. I then had a forum member, who purchases a lot of Pertex fabric, contact his rep. The rep's spec for the fabric was less than 1.97 CFM.

At a 7 MET exertion level (UL backpacking average), in average summer mountain temperatures and wind conditions, most people find the Houdini air permeability the optimal windshirt available. I measured the spring 2012 version of this windshirt at 35.8 CFM. The reason its air permeability is optimal is that this is the level of air permeability that will JUST PASS the AVERAGE EVAPORATED SWEAT moisture while UL backpacking. More air permeability than provided by the Houdini is not a wise choice for most people.

As air permeability goes up, wind resistance and external moisture protection goes down. More air permeability than is required to pass through your sweat is not a benefit. The key to selecting optimal windshirt air permeability is matching the air permeability that will just pass your average evaporated sweat level without venting. Venting can then be used for augmentation.

A windshirt that would never limit your maximum possible work potential requires ~400 CFM air permeability and would be worthless for protecting you from any wind or moisture. It is a balancing act.

Edited by richard295 on 05/28/2013 11:03:22 MDT.

Michael Cheifetz
(mike_hefetz) - MLife

Locale: Israel
any posts re CFM data on 11/26/2012 13:13:01 MST Print View

@richard
by any chance did you ever measure the Montane Fetaherlight? is there a post here with more data RE other designs apart from the Houdini and Boreas?

10x
Mike

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: any posts re CFM data on 11/26/2012 13:40:36 MST Print View

Mike,

I didn't measure the Montane Featherlight air permeability. Any article and most forum posts I have seen on BPL has provided only subjective windshirt air permeability ratings. Unfortunately, most manufacturers also do not provide air permeability test data.

You can roughly ball park a relative position estimate by comparing the windshirt you are interested in to one of the three low, medium, and high references, that I provided, using a “air suck test”.

Edited by richard295 on 11/26/2012 14:05:24 MST.

Michael Cheifetz
(mike_hefetz) - MLife

Locale: Israel
no access ...unfortunately on 11/26/2012 14:01:27 MST Print View

@richard - unfortunately no real access to that type of gear here in israel :(

RE pertex - Montane uses "pertex microlight" - is that the classic?

RE Houdini - i assume that is the older model...i gather the new one is less permeable
Is the driclime similarly specd?

M

nian zhang
(thotwielder) - F
Re: Re: how breathable a wind shell is on 11/26/2012 14:06:36 MST Print View

Richard,

Very interesting figures, you are a scientist :)

My pertex shell is Montane feather light smock. If it's only 3 CFM then may be it's not enough for me. Saw that Houdini a lot, maybe will get one. Do you by any chance test other material like Marmot driclime?

Thanks for those figures, very informative.

Nian

Justin Baker
(justin_baker) - F

Locale: Santa Rosa, CA
Re: how breathable a wind shell is on 11/26/2012 14:26:29 MST Print View

It should be breathable. I wear my sierra designs kenosha wind shirt while sleeping and I never wake up with damp clothes. I can't say that about sleeping with a rain jacket on.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: Re: Re: how breathable a wind shell is on 11/26/2012 15:15:50 MST Print View

I am going to pass on creating forum posts dealing with the testing of the less mainstream windshirts that were released in various years.

I tested the Houdini versions for these years:

2008 Houdini = 47.01
2009 Houdini = 43.85
2010 Houdini = 38.12
2011 Houdini (Military Special Edition) = 35.42
2012 Houdini (Spring Version) = 35.80

I tested the Marmot DriClime for only one model year:

2010 DriClime = 24.25

Both of these windshirt brands are near the sweet spot of air permeability required for UL backpacking but, the fixed thermal insulation layer of the DriClime limits its versatility.

One thing clear to me is the term "windshirt" is very nebulous without knowing the model / year / and its respective air permeability.

Edited by richard295 on 11/26/2012 16:54:30 MST.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: Re: Re: Re: how breathable a wind shell is on 11/26/2012 17:55:51 MST Print View

I thought that Dave did a good job on his two windshirt SOTM articles but, based on the published Boreas material specification; it was too porous, too heavy, and too prone to snagging to garner an "A" rating, for most people, in the spectrum of UL windshirts. I acquired one and lab tested it to see if how it compared to my preconceived notions.

Its air permeability tested about half way between the Houdini and Squamish. At that air permeability rating, its equivalent breathability competitors were the myriad Polartec Wind Pro jackets. Since those jackets weigh at least 2x more, I was forced to acknowledge that it could conceivably be considered UL relative to them with comparable weather resistance.

There is no magic windshirt; as air permeability goes up, external wind and water resistance goes down. Whichever windshirt just barely achieves the necessary moisture transport for your average MET (7 for backpacking) is the optimal solution.

For my personal backpacking use, a layered Houdini (with Velcro added to fix the big wrist problem) gets my A rating. The material used is an EPIC process which keeps the DWR active for the life of the garment. At 7 MET (backpacking average) it needs to transport ~8,000 – 10,000 g/m2/24 h which it does. In contrast, an eVent jacket can only transport about 5,000 g/m2/24. If you are a jock like Dave C. your average MET would be higher and hence the attractiveness of a garment like the Boreas.

For highly aerobic activities such as jogging, a layered Squamish would get my A rating. This option passes transports more body moisture and has better external wetness protection. The material is a weave in contrast to a knit like the Boreas; as a result it is much less prone to snagging during bush walks.

Jim Colten
(jcolten) - M

Locale: MN
Re: how breathable a wind shell is on 11/26/2012 18:05:10 MST Print View

Thanks for the fantastic post, Richard.

Yet another example of "there is no single best ______ for ______".

Far too few product evaluations acknowledge the variability between individuals and also variability between different conditions. This one goes out of it's way to hilite those differences.

edit: "shoot first, aim later ... kinda;-)" after posting I took the time to peruse the entire thread and ... Richard has more than one post here that rates my appreciation.

Edited by jcolten on 11/26/2012 18:07:55 MST.

Tom Kirchner
(ouzel) - MLife

Locale: Pacific Northwest/Sierra
Re: Re: Re: Re: Re: question for Richard N. on 11/26/2012 18:23:44 MST Print View

"For my personal backpacking use, a layered Houdini (with Velcro added to fix the big wrist problem) gets my A rating. The material used is an EPIC process which keeps the DWR active for the life of the garment."

What do you mean by a "layered" Houdini? It is a term am unfamiliar with. Also, is the Houdini made with an EPIC style encapsulated thread?

Many thanks for your input.

Tom

Aaron Croft
(aaronufl) - M

Locale: Alaska
Apples to Oranges on 11/26/2012 18:32:14 MST Print View

In comparison to Richard's testing, after trying both the Houdini and Boreas, I found that I consistently overheated in the Houdini in moderately cool and windy temps. On the other hand, I have found the Boreas to be a perfect top for wearing by itself or layering while climbing, hiking, or running. Like Richard mentions, I think this is where personal preference, body chemistry, and climate come into play, as I run a little hot and don't choose a windshirt for its DWR.

Edited by aaronufl on 11/26/2012 18:34:11 MST.

David Chenault
(DaveC) - BPL Staff - F

Locale: Crown of the Continent
re: windshirts on 11/26/2012 18:45:01 MST Print View

Thanks Richard, I'm not a numbers guy (obviously), so your thoughts are highly valuable.

I did give the Houdini an A-, which I'd change to an A if the stock shell fit like my modified one. Having both is a nice quiver. The Houdini gets used a lot this time of year. A wool t-shirt, Cap 4 hoody, and Houdini is great for steady work in mixed weather (e.g. snowbiking and XC skiing during an intermittent snowstorm this weekend).

Pertex Classic (aka Pertex 5 or 6) is a lot heavier, and I assume less breathable, than either Microlight or Quantum. Good to do your research here.

Edited by DaveC on 11/26/2012 18:46:45 MST.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: Re: Re: Re: Re: Re: question for Richard N. on 11/26/2012 19:03:59 MST Print View

Tom,

I used the term layered to differentiate the Houdini use from the DriClime in my prior post. I meant that I layered a different base layer under it based on the expected conditions versus always using a moderately thick layer under it like is built into the DriClime.

See http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=6696&skip_to_post=47736

Back in 2007 I first pointed out that my micrograph indicated that the threads were encapsulated as they are in the EPIC process.

Mike R
(redpoint) - F

Locale: British Columbia
Patagonia Houdini on 11/26/2012 19:26:00 MST Print View

I can post again - cool.

Personally, I find Gore-Tex to be one of the biggest scams around. It's breathable compared to a cheap PU coated raincoat, but it's not very breathable compared to a soft-shell. I've never been impressed by W/B fabrics since their inception in the late 1980s. My W/B jacket/pants stays in my pack and is only used when/if the weather turns foul.

I bought a Patagonia Houdini wind shirt in 2010 and it's probably the most versatile piece I own. It's DWR finish is excellent - will handle mist, very light rain, and snow. It's extremely breathable so you don't get hot and clammy like you do while wearing a W/B shell. For me, it excels when I'm doing things like climbing up a mountain on skis, where I need to break the bitter wind, but Gore-Tex will just roast me. It's the perfect garment. On a day where I'm doing a lot of up-hill climbing on skis or mountaineering, I'll wear Patagonia Guide Pants, syn underwear, syn base layer top, and the Patagonia Houdini jacket. When I stop, I'll toss on a parka.

In the summertime, if the weather window is looking decent, the houdini is all I'll carry for wind.

Edited by redpoint on 11/26/2012 19:31:37 MST.

Tom Kirchner
(ouzel) - MLife

Locale: Pacific Northwest/Sierra
Re: Re: Re: Re: Re: Re: Re: question for Richard N. on 11/26/2012 20:34:57 MST Print View

"I meant that I layered a different base layer under it based on the expected conditions versus always using a moderately thick layer under it like is built into the DriClime."

This and the link make things perfectly clear. As always.

Thanks again, Richard.

Mark Verber
(verber) - MLife

Locale: San Francisco Bay Area
Re: how breathable a wind shell is on 11/26/2012 20:42:21 MST Print View

Thanks for the post Richard! I find myself needing to replace my Houdini. I was thinking about getting the Squamish from a feature perspective, now that I see the higher CFM, I am sure the Squamish will be my next windshirt given past experience comparing your and my comfort set point.

I don't suppose you have the CFM for Equilibrium used in the Rab Alpine Jacket Pullover?

--Mark

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: Re: how breathable a wind shell is on 11/26/2012 21:08:02 MST Print View

Mark,

Pertex specs that fabric at 10 CFM. The other Pertex fabrics I have tested were close to their specs.

Knowing how little insulation you require compared to me makes me think you would be happy with the Squamish.

Mark Verber
(verber) - MLife

Locale: San Francisco Bay Area
Re: Re: Re: how breathable a wind shell is on 11/26/2012 21:38:09 MST Print View

> Pertex specs that fabric at 10 CFM.

Hmm... what confuses me is that my memory is that the Equilibrium in the Rab Alpine was more air permeable than my Houdini. Alas, I can't verify my memory because I sold my Rab Alpine and haven't yet purchased the smaller size yet.

--Mark

Brendan Swihart
(brendans) - MLife

Locale: Fruita CO
Squamish on 11/26/2012 21:51:58 MST Print View

Richard,
Is that CFM for the current Squamish? Looks like there's a couple different names from different years of the fabric used (gossamera, luminera) and I'm wondering if it's still that breathable...

eric chan
(bearbreeder) - F
dead birds on 11/26/2012 23:30:19 MST Print View

i have a celeris and i find it quite breathable ...

windshirts are a mixed bunch ... some are no more "breathable" than a good WPB ... others are much more so ...

the only way to find out is to test it in the store and outside ... unless you have a book full of real testing ;)

it also depends on YOU and what you do ... for example scrambling up a steep hill vs. prancing around some flat trails ...

one question to ask is "do you really need a windshirt" ... if its not that windy, you can usually get by even when cold with a light breathable fleece ... if its really windy, youll get some cooling effect off that and one could just wear the WPB with zippers half open ...

know your gear, test it, use it ... dont think that you NEED any windshirt or any particular item because it is "popular" on BPL ...

Roman Vazhnov
(joarr) - MLife

Locale: Russia
CFM on 11/27/2012 02:25:37 MST Print View

Numbers of CFM, provided by Richard Nisley do not correspond with "traditional" numbers, provided by manufacturers, etc. For example for Squamish it was 7 CFM, for traditional fleece - around 200 CFM and so on. In my simple unscientific test by blowing through the fabric Squamish was significantly less air permeable than fleece. And i thought Boreas (and similar MHW Chocklite) is more air permeable than Squamish. But i don't have Squamish right now to repeat test again. I am confused.

nian zhang
(thotwielder) - F
Re: Re: how breathable a wind shell is on 11/27/2012 04:42:05 MST Print View

Great inputs from everyone. I can imagine a breathable wind shell can be useful a lot of time if not all the time and since it is so light. I will probably get a Houdini when I can get it on sale. Or a Rab celeris, or a Marmot ether driclime. I kind like the mesh vent on Marmot ether and it can be a midlayer under my shell since I will bring my shell anyway.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: CFM on 11/27/2012 06:32:38 MST Print View

Roman,

Windshirt fabrics for the same model can change from year to year. Unlike the Houdini, I only checked one model year for the Sqamish. Polartec fleece types are a good reference because they are consistent. The classic fleece tests at 254 CFM and newer double face versions test at 325 CFM.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: Squamish on 11/27/2012 06:47:12 MST Print View

Brendan,

I have not tested any of the recent Squamish model years. Unlike the Hudouni, I don't know how the value changed for each model year. The one I tested has the Acteryx model listed as: Squamish Windshell - Men's – ARCTERYX; Item #: 202600; Price: Reg. $139.00. In their marketing description they called the fabric Gossamera nylon.

Don Wilson | 2008-04-08 14:49:00-06 reviewed the same windshirt in BPL. He described the breathability as, "I was pleased with the breathability of the fabric, which seemed on par with similar windshells. What I like best about the fabric is the soft drape and comfortable feel against my skin. The fabric is less smooth than the fabric in many lighter windshells, and doesn't make me feel like I am wearing a plastic bag."

I found that same air permeability in the Squamish Windshell as the MH Canyon shirt and the RR Adventure shirt. Both of these shirts are designed for summer use.

Edited by richard295 on 11/27/2012 08:32:34 MST.

nian zhang
(thotwielder) - F
Re: Re: Squamish on 11/27/2012 07:24:53 MST Print View

Hi Richard,

It's interesting to know the Squamish has similar breathability as a normal shirt. Does it mean they have similar wind resistence? If it's the case, does it mean I can just use base layers to achieve the same effect? E.g. begin with a T shirt, if windy put on a long sleeve shirt. Can you test the CFM of a two bases combo like this? I am asking because I also always bring two base (T + long sleeve).

Nian

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: dead birds on 11/27/2012 08:00:14 MST Print View

Eric,

I am confused by the technical terms you mountain climbers use to describe air permeability. How does "quite breathable" compare to "windproof",” “wind-resistant,” and “breathable”? (smile)... just kidding.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: Re: Re: Squamish on 11/27/2012 08:21:07 MST Print View

Nian,

I most recently answered your question on combining air permeability layers here:
http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=26774&skip_to_post=593635#593635

The Squamish I tested would have similar wind resistance (aka air permeability) to the main nylon fabric used in either summer shirt I mentioned. The summer shirts have an open mesh panel on the sides to achieve more air permeability and the Squamish has a deep center zip.

Edited by richard295 on 11/27/2012 08:33:32 MST.

Brendan Swihart
(brendans) - MLife

Locale: Fruita CO
CFM measurements on 11/27/2012 08:36:48 MST Print View

Thanks for all the info, Richard; it's appreciated.

I'm curious if there are different types of CFM measurements...in the post you just linked (from 09) you list the Houdini as 5 CFM compared to the 40+ in this thread (including model yrs 08 and 09). Are those different types of measurements?

Roman Vazhnov
(joarr) - MLife

Locale: Russia
Re: Re: CFM on 11/27/2012 09:02:52 MST Print View

Richard, yes i understand that the same model may have different fabrics from year to year, even fabrics with the same name can have different characteristics within the family. I wanted to say (+1 to Brendan) - may be there are different methodics? Because this numbers (around 100 for windshirt) are rather great. People used Squamish for winter backcountry travel and so on, and reviews said that air permeability was on pair with similar windshirts.

For example this are the numbers from your post in 2009:
"Polartec Windbloc 0 CFM… PU layer
Gore Windstopper <2 CFM Porous Teflon membrane without the Gore PU layer
eVENT <2 CFM Porous Teflon Membrane (hard shell product for ref only)
Driclime windshirt 3 – 5 CFM
Patagonia Houdini windshirt 5 CFM
Polartec Powershield 8 – 16 CFM Perforated Membrane
Polartec Windpro 60 CFM
200 wt Fleece 200 CFM"
cfm

Which numbers are correct? Maybe the numbers from the table above are from manufacturers, not from independent test?

Another assumption - was it (Squamish) new? Maybe PU coating inside was worn out?

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: CFM measurements on 11/27/2012 09:09:11 MST Print View

Brendan,

There is only one standard for air permeability. In contrast, there are a large number of different MVTR breathability standards. When comparing windshirt fabrics to eVent fabrics only air permeability is relevant.

In '09 I didn't own an air permeability tester. I purchased it in 2011 and tested the Houdinis from prior as well as subsequent years. In that old post I used the Patagonia Houdini air permeability specification that was in a Patagonia Power Point presentation that Mark Verber posted. Hopefully Mark can tell us the year of origin for that presentation.

Edited by richard295 on 11/27/2012 09:11:32 MST.

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: Re: Re: CFM on 11/27/2012 09:20:35 MST Print View

Roman,

I 2009 I didn't own my own air permeability testing equipment and had to rely on vendor specs. In early 2011 I purchased an air permeability tester and since then I have used the old "trust but verify" approach to vendor's air permeability ratings (smile).

Roman Vazhnov
(joarr) - MLife

Locale: Russia
Re: Re: Re: Re: CFM on 11/27/2012 09:46:36 MST Print View

Thank you, Richard. Can you consider the opportunity to post the table with cfm for all garments you have tested?

eric chan
(bearbreeder) - F
Re: Re: dead birds on 11/27/2012 11:52:13 MST Print View

well richard ...

if im soaking in sweat more than a balding middle age man in a vegas porn convention ... it aint breathable ;)

absolute "windproofness" isnt usually an issue as youre putting on a belay jacket when not moving anyways ... and you may also have a light synth puffy when moving over technical terrain

Eric Blumensaadt
(Danepacker) - MLife

Locale: Mojave Desert
A little respect for balding, middle aged men please! on 11/27/2012 14:11:52 MST Print View

I'm not balding and I'm well past "middle age" but I DO live in 'Vegas. You mean they have porn conventions in 'Vegas? Geeze, now THAT would make me sweat so maybe I shouldn't wear my windshirt when I go.

"Seriousnessly", when hiking in mountains I always wear a long sleeved poly or nylon shirt for UV protection. That shirt is the only one I carry other than two poly T-shirts. Thus no DEDICATED windshirt. Of the four shirts I have the "511" brand nylon shirt is the most windproof and the polyester REI Sahara the least. The altitude and season dictate which one I take.

But still they provide enough protection that I can wear a medium weight (200 wt.) polyester fleece vest beneath them on cool, windy days and be just fine. Their vented backs are covered by my pack. Around camp the eVent parka goes on.

Mark Verber
(verber) - MLife

Locale: San Francisco Bay Area
Re: Re: CFM measurements on 11/27/2012 23:50:16 MST Print View

> that old post I used the Patagonia Houdini air permeability specification that was in a
> Patagonia Power Point presentation that Mark Verber posted

it was 2005. The Patagonia windshirt back then was called the dragonfly. My memory is that the first generation houdini which came out in 200? used the same fabric but a slightly different cut / zipper configuration.

--Mark

Peter Fokkinga
(nitto)

Locale: the Netherlands
autumn 2012 Houdini on 11/29/2012 12:05:19 MST Print View

Richard,

Do you intend to test the new autumn 2012 version of the Houdini (1.2-oz 10-denier fabric) as well?

I fear its "blocks more wind than the previous version" feature, in combination with the slimmer fit, could mean it is actually a step back from the previous version :(

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: autumn 2012 Houdini on 11/29/2012 12:42:12 MST Print View

Peter,

I will test a Autumn 2012 when I get access to one. I don't have a scheduled date.

Michael Cheifetz
(mike_hefetz) - MLife

Locale: Israel
Pertex microlight - confusing answers??!?! on 11/30/2012 04:19:40 MST Print View

So I wrote pertex directly and Montane as well and received the below answers (that I am not sure about...)
Pertex:
Thanks for contacting Pertex®
Air permeability of Pertex® Microlight is less than 3cfm.

Montane:
The figures we have from Pertex for Microlight are 1.0cc max (JIS L 1096/ ASTM D737).


anyone can figure this out? how does it sit within the scale @nisley measured the Houdini??


there is also this post by @nisley
http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=44347

Quoting 15.59 for the same pertex

Richard Nisley
(richard295) - M

Locale: San Francisco Bay Area
Re: Pertex microlight - confusing answers??!?! on 11/30/2012 13:00:56 MST Print View

Mike,

The ASTM D737 standard on page 3 says, "11.1 Air Permeability, Individual Specimens—Calculate the air permeability of individual specimens using values read directly from the test instrument in SI units as cm3/s/cm2 and in inch-pound units as ft3/min/ft2, rounded to three significant digits.”

Pertex’s response of <3 CFM is the air permeability reading using the ASTM D737 imperial representation and the Montane’s response of 1.0cc max is the equivalent ASTM D737 scientific representation which is 1.97 CFM; they are effectively equivalent values.

15.59 CFM is what I measured for the Microlight fabric used in the Montane Lite-Speed version that Ryan Jordan, Roman Dial, etc. selected for use in the 2006 Artic 1000 trip. The hang tag on the fabric I tested said, “Pertex Microlight E.B.P. Fabric for Body”.

Also in 2006 Pertex sold the company to Japan based Misui. At the time of the sale there were at least 9 Quantum variants and 5 Microlight variants with different weights and air permeability ratings for each one. The Quantum variations offered a smaller air permeability range than the Microlight variations. Your 2012 Pertex Microlight product specification is different than the 2006 variant that I tested.

The ASTM D737 standard tests I conducted, for multiple years of Houdinis, use the same CFM test value representation as Montane and Pertex.

Edited by richard295 on 11/30/2012 13:19:43 MST.

O S
(puddlemonster) - F

Locale: SF Bay - East Bay
To Richard Nisely on 12/12/2012 19:37:16 MST Print View

Just found out the new Houdinis (as of mid 2012) aren't siliconized, they are treated with a DWR. (probably still done in the Epic process, i.e. woven from preg'd yarn)
Might look the same under microscope, but it's not silicone.
It does contain some flourocarbons, so I opted to avoid it.

Edited by puddlemonster on 01/11/2013 17:07:47 MST.

Simas Peciura
(pechius)
Re: To Richard Nisely on 03/18/2013 04:28:05 MDT Print View

How did you find that out?

Rob P
(rpjr) - M
Different Squamish Materials on 03/18/2013 15:42:49 MDT Print View

Don't laugh....I have 2 of these!

I keep the blue one for the most part in my golf bag, folded into its chest pocket. It is a "stretchy" material. I also have a blaze orange one I like to wear for fall hiking (keeps me visible in case hunters are around)...It is clearly a different material...less stretchy and more like a traditional "windbreaker".

Richard, If you have any interest in testing these different materials, let me know.