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Western Mountaineering on water resistant down and Pertex fabric
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Sam Farrington
(scfhome) - M

Locale: Chocorua NH, USA
Rubbish on 10/29/2013 22:55:39 MDT Print View

Re: "... goose down really, is naturally very water resistant and it is not easy to get completely wet in any real life scenario."

Agree with Bob G. It might be more accurate to say, "and it is not easy to keep it dry in real life wet weather scenarios."

But we do go to the trouble due to its superior efficiency as an insulator.

But if I could get the same insulative value and weight from a synthetic, down would be history. Not that I like geese or anything.

Mary D
(hikinggranny) - MLife
Western Mountaineering on water resistant down and Pertex fabric on 10/29/2013 22:55:46 MDT Print View

Yes, if down gets wet, it's not much good as insulation.

What the purveyors of synthetic insulation don't say is that wet synthetic insulation is just as cold! Been there, done that! Regardless of what kind of insulation you use, it's critical to keep it dry.

Sam Farrington
(scfhome) - M

Locale: Chocorua NH, USA
wet synthetic insulation on 10/29/2013 22:58:47 MDT Print View

Mary D,
Must respectfully disagree. Have wrung out synthetic bags (when I was too young and stupid to keep them dry), and they kept me warm. Down? NYET.

eric chan
(bearbreeder) - F
Re: wet synthetic insulation on 10/29/2013 23:10:09 MDT Print View

folks ... this has all been argued before in the last BPL article on the subject

basically synth deals with internal condensation much better and allows one to dry out damp layers underneath ...

wet synth sucks, but i find i can just wring it out and dry it decently to damp with bodyheat and a hawt nalgene


Dale Wambaugh
(dwambaugh) - MLife

Locale: Pacific Northwest
Re: Down can get wet and useless on 10/29/2013 23:54:57 MDT Print View

It not just that down is useless when wet, it STAYS that way. If you build a good fire and dry the bag, tending it closely, with it suspended on sticks, poles and/or lines, shaking it to separate the lumps and fluff it back to life. That implies hours of work, waiting, gathering firewood and assuming that it would stop raining or snowing. Ice read so many times about someone spreading out their down gear in the sun on breaks to get completely dry from simple moisture build up overnight from body and dew. Fat chance of that happening in my neck of the woods. The rain will come and even if it stops you will have 50F, 85% humidity, everything around you wet with dew and not a glimmer of direct sunlight. Whatever gets wet stays that way for the duration of the trip.

Leave the feathers on the bird!

Roger Caffin
(rcaffin) - BPL Staff - MLife

Locale: Wollemi & Kosciusko NPs, Europe
But what does it mean? on 10/30/2013 01:53:53 MDT Print View

> Patagonia's method of molecular level deposition of DWR
And exactly WHAT does this mean?

To me it reeks of yet more marketing spin. Of course molecules are deposited on the surface, but that applies to any chemical treatment being applied to any surface. When companies resort to marketing spin with long unexplained technical jargon, I tend to dismiss ALL their claims.


Dustin Short
(upalachango) - MLife
Re: But what does it mean? on 10/30/2013 01:58:44 MDT Print View

+1 Roger!

Thanks for saying it so I didn't have to!

Roger Caffin
(rcaffin) - BPL Staff - MLife

Locale: Wollemi & Kosciusko NPs, Europe
How easy is it to wet down? on 10/30/2013 02:07:01 MDT Print View

You know, we have quite a few articles on the performance of down gear. Read them: there has been a lot of testing done. For a start, many have noted that with a good DWR on the surface fabric, it is actually quite hard to get down gear wet.

I guess if you cowboy camp on top of a mountain while it is snowing things may happen, but in my book that is trying for a Darwin Award. Just my opinion.

Don Wilson wrote in an article on 'Drying Characteristics of Select Lightweight Down and Synthetic Insulated Tops":
"A surprise discovery - the down Flash vest recovered loft as quickly as the synthetic Micropuff and after 30 minutes of drying its loft exceeded the Micropuff's."

And there's lots more besides that.

Always remember: it;'s a harsh commercial world out there, and the synthetics guys know their product is inferior to down, so they go for any claim they can come up with. Be cynical about them. The same thought applies to all the wonder-marvel DWR treatments being spruiked. They don't have to be any better; they just have to con you into believing.


Woubeir (from Europe)
(Woubeir) - F - MLife
Re: How easy is it to wet down? on 10/30/2013 04:22:34 MDT Print View

I agree. Ones down is completely soaked, it is a problem, and you can get it soaking wet But the first thing that popa up in my mind is: how to get it soaked in the first place ? I have used down jackets, bags, ... in some pretty miserable weather and I never got it soaking wet in a non-testing situation.

BTW, nice remark about the Darwin-award.

Tom Lyons
(towaly) - F

Locale: Smoky Mtns.
I like the old, I might like the new, too. on 10/30/2013 07:23:00 MDT Print View

My practices include methods for keeping my down dry and lofted to the best extent possible, because it provides the best warmth with the least carry-weight and best compressibility. Keeping it working to its best is important to get the most results out of it with the least bulk.

I like the regular down quite a lot.
I might like the new water-resistant down just as much, or more, depending on just how much real-world improvement is actually seen from it.

It concerns me that it might lead to lazy practices of not taking care to keep the down lofty, relying on "claims" which may or may not turn out as well as hoped in real world circumstances, and result in reduced performance.

There are still a lot of unanswered questions about this stuff, although I admit that I am intrigued to find out what it can really do(and what it can't).

Woubeir (from Europe)
(Woubeir) - F - MLife
Re: I like the old, I might like the new, too. on 10/30/2013 07:48:56 MDT Print View

An another question: is the higher price worth it ?

David Olsen

Locale: Steptoe Butte
Down in the Olympics on 10/30/2013 07:58:16 MDT Print View

I have used a down bag, January on the coast trail in the Olympics. Rained pretty much all the time and when it wasn't there was fog. Part of the time I used a polarguard overbag and was very toasty. Otherwise I slept warm enough, save one night cowboy camping in a draw in a windy fog. Never got my bag sodden. I feel if I had carried a down bag with enough down to match the weight of a sythetic bag, I would have been warm even on that one foggy night.

Brian Lindahl
(lindahlb) - MLife

Locale: Colorado Rockies
Re: Re: Down can get wet and useless on 10/30/2013 10:06:51 MDT Print View

> It not just that down is useless when wet, it STAYS that way

This is exactly why I don't really understand the purpose of a DWR-coated down (i.e. Downtek). DWR sheds a bit of precipitation - that is all. If you have a lining on your shell, that's shedding the moisture. If water gets through the lining, either it's wetted out, or it was pressed through (in both cases, having another DWR layer over the down won't help much - it'll wet out or be pressed into the down, just like the lining).

As anyone who's ever played with non-waterproof DWR garments will tell you, the DWR does absolutely nothing once an item gets wet, and does absolutely nothing in humid environments. Nor does it help when moisture is pressed into the garment.

So then... what exactly does DWR'd down buy you? In my experience, I would gather not much at all. It sounds good on the marketing brochure though. Call me skeptical.

Edited by lindahlb on 10/30/2013 10:09:41 MDT.

jeffrey armbruster
(book) - M

Locale: Northern California
"Western Mountaineering on water resistant down and Pertex on 10/30/2013 10:17:15 MDT Print View

Actually I'd really sit up and take notice if Patagonia managed to deposit their chemical protection WITHOUT involving molecules.

eric chan
(bearbreeder) - F
tests on 10/30/2013 10:28:10 MDT Print View

many of the BPL drying tests on down are done assuming one has proper "drying conditions" ... ie the sun

ive not seen a BPL test yet done on trying to dry down without the sun or a decent breeze ... id would love to see one ...

and of course, most of these BPL tests are on THINNER garments with a few OZ of down, not big thicker puffies or sleeping bags ...

also just because a WM flash dries quickly doesnt mean some other jacket will ...

The wet performance we observed in the MontBell Down Inner jacket supports the assertion that higher volumes of down and a less breathable shell will reduce the wet weather performance of a down garment. The Down Inner jacket has a higher volume of down than the Flash and lofts to 2.8 inches of double layer loft. Its shell material is MontBell's Ballistic nylon. Ballistic nylon threads are calendared. They are heated, then flattened and widened. This improves abrasion resistance and reduces down leakage, but also reduces breathability and slows the drying rate of the Down Inner jacket. (The calendared fabric is closer to a non-breathable/waterproof fabric). The Flash vest with non-calendared fabric reached 1.3 inches of double layer loft after 30 minutes, exceeding the loft of the synthetic Micropuff. But the MontBell Down Inner Jacket with calendared fabric took approximately 100 minutes to recover to 1.3 inches of loft.


Synthetic insulation is far superior to down when both are fully saturated.


Most other down-filled products will not recover from becoming wet as quickly as the Flash vest due to more down mass in relation to surface drying area..

here is a real life BPL description of the effects of internal condensation on down when you CANT dry it due to lack of sun even in mild conditions ....

The next several days were no better. After a half-day in the town of Packwood, we were back on the trail with dense clouds and no views. Our tents were soaked every morning from condensation, and it became harder and harder to dry our things out every day. My sleeping bag’s loft started to weaken little by little as humidity collapsed the down, and I was forced to sleep in layers even on relatively warm nights. Those warm nights, however, began to vanish soon after Packwood. With 100% humidity and temperatures dipping into the high thirties each night, my main motivation became the next stop in town.


In the morning, we had the now all too familiar experience of packing tents that were soaked with rain on the outside and condensation on the inside. Then, as we walked up the trail, our clothes became saturated by what Tangent began to refer to as the “car wash effect.” Even with only small amounts of rain in the night, the water collected on leaves of bushes and shrubs, which leaned into the trail and sprayed us as we pushed through the mess. Every morning started with drenched feet and pants, depending on how much rain gear we felt like wearing.

from another BPL article ....

On a multi-day trip, critical attention must be paid to minimize the moisture that accumulates in your sleep system as each night passes. Weather permitting, you should take the opportunity to air-dry your sleeping bag and bivy sack every morning. This technique is important even in sub-freezing winter conditions - but only in the presence of bright sunlight. Solar radiation will provide the heat energy required to drive the evaporation of moisture from your gear


But alas, as weather is notoriously uncooperative, you should consider your clothing and sleeping bag loft as a consumable but renewable resource and take steps to actively manage it like you would, say, your drinking water. Be opportunistic and dry gear whenever you can on an extended trek!

again what i would love to know is short of having a synthetic overbag and an excess of heat (fire, hawt nalgene) how do you dry down without the sun when your sleep/clothing system is already at the limit of its temperature rating

now that would be an AMAZING BPL article


Andrew F
(andrew.f) - F - M

Locale: San Francisco Bay Area
Re: Western Mountaineering on water resistant down and Pertex fabric on 10/30/2013 10:40:09 MDT Print View

A very reasonable and responsible answer from WM. I too have my reservations about DWR down. High quality down fill is one of those products that is already so good, there would be plenty of ways for DWR down to fall short.

I recently got a Zpacks quilt and decided to try out treated down, as a sort of experiment. I may live to regret it, but so far, it has been performing well. My testing only spans about 4 nights so far, but after an extra cold night spent with the quilt covering my face breathing lots of condensation into it, it held up much better than untreated down. There was no loss of loft on the section over my face despite visible beads of water inside, and the quilt dried out significantly faster than my untreated bags do. When I do this with my untreated down quilt I end up with two layers of wet nylon over my face with clumpy down that takes a long time to dry. Once I have more experience with it I'll report my results. Of course untreated down has many many years of useage behind it so it will take awhile to see how it stacks up.

Just a note on the testing procedure: Just because shaking down in a container with water does not mimic the exact real world useage does not mean the test is worthless. Many test standards use a somewhat unrealistic configuration simply as a basis for performance characterization. For example, UV exposure for nylon equipment: gear is artifically aged at high humidity, high heat, under a strong UV lamp that is hundreds of times stronger than the UV experienced from the sun, to accelerate the aging process. But that test is very useful for comparing UV resistance of different synthetic fibers even if it does not tell you the lifetime under real-world usage.

Greg F
(GregF) - F

Locale: Canadian Rockies
Humidity and Vapour on 10/30/2013 12:31:58 MDT Print View

Has there been any studies on DWR downs performance in high humidity or wetness from water vapour from sweat. To me this is the key point for the performance of DWR down. Anyone can keep there down bag dry from the outside. In the moisture sources from the inside where improvement could be made.

So I appreciate the annecdotal reports above that the bag performed better when people breath into. Is there any research or testing that has been done in this area.

I would think that putting two garmets in a room with high humidity for a few days and monitor loft loss would be a start.

Roger Caffin
(rcaffin) - BPL Staff - MLife

Locale: Wollemi & Kosciusko NPs, Europe
Re: tests on 10/30/2013 16:21:26 MDT Print View

> how do you dry down without the sun when your sleep/clothing system is already at
> the limit of its temperature rating
Seems to me you might have made a bit of a mistake in choosing your gear in this case. Going SUL is all very well, provided the conditions are suitable. Sometimes they aren't.

We have had good success in drying a quilt in the snow by layering another quilt over the top. The inner quilt does dry out, but the outer quilt may get some condensation (or frost!) inside the outer shell. Then you have to deal with that. This is a good argument for using a two light layers rather than one heavy layer.

Hum ... I wonder how one would go with a single layer of fabric (to catch the condensation) over a very good DWR shell? Probably only work under a very limited temperature range. Pity.


Sam Farrington
(scfhome) - M

Locale: Chocorua NH, USA
WR down on 10/30/2013 17:23:38 MDT Print View

Eric and Dale,
My experiences parallel those you relate in your posts. Thanks.
The word anecdotal is often used by folks who wish to disregard something.
Another tactic is the classic blame the victim.
So when my down bag gets soaked, it is my fault and it's anecdotal.
You can recite instances till he** freezes over, and it's all anecdotal and your own fault.
Folks whose experience is limited to no worse than an afternoon and night of rain will never take you seriously. And why should they, if they stick to sunny Cal.
Or even to the Southwest, where we have been interminably told to start early to avoid getting caught in the afternoon thunderstorms - no mention of endless days of constant pounding, drenching rain or the like.
However, global climate change is creating some bizarre weather where you wouldn't expect it.
We can't always be ready for every conceivable form of the worst nature can throw at us, but there's no reason not to use the most protective UL gear we can afford to buy or make. Makes for a much more enjoyable trek, and greatly reduces the likelihood of having to throw in the towel and bag a trip - most depressing IMO.

P.S. Am totally baffled by those who appreciate the endless blah-blah-blah of marketers. Before listening to a single word from any one of them, I want to see their trekking history (not gonna happen). Nimblewill I will listen to all night (figuratively speaking, by reading his accounts).

water on 10/30/2013 17:37:41 MDT Print View

Anyone that has ever washed a down bag, knows what a wet bag looks like. Its pretty pathetic, about the size of a football, MAYBE, when you take it out the washer.

Down is simply one of those things that must stay dry at all costs in cold conditions, PERIOD.

You should also not have only down as insulation with a down bag. You should use a synthetic puffy, and fleece as well. Unless you hike in the desert of course.

Dridown doesnt change the game. It just makes gross water uptake slower.