Down, Synthetics & "Hydrophobic" Down

Have you had experience using "hydrophobic" down and if so, how did it work for you, compared to your experiences without it ?

Since this forum is the only backpacking or outdoor gear forum that I visit, I don't know the extent to which this subject has been discussed elsewhere, so bear with me, please.

I'm familiar with the theory and process of "hydrophobic" down material but not so much on the subjective experiences of using it.

My Background with Down & Synthetics (disregarding earlier days with woolens):

DOWN: My sleeping bags have exclusively been down-filled, with water-resistent shells. In the 80's, early 90's always custom bags from Feathered Friends (I'd go down to the old factory near the old, original REI to order & pick up). In the later 90's til now, lightweight Western Mountaineering bags. Down bags have worked well for me, always cared for properly both in storage and while in the backcountry. There have been times, however, when I noticed the down starting to sag, where perhaps the "hydrophobic" down would be useful.

One example backcountry trip - in mid-August, a multi-day 70+ mile section of the PCT from Steven's Pass to Snoqualmie Pass - we immediately encountered unseasonable freezing rain & snow which continued relentlessly the entire trek. No time to lay out the bags to dry. I had a WM Ultralite at the time. Anyway, even with utmost care, toward the end of the trip the down was dampened and the next to last night (freezing with snow), I was thankful for my Primaloft parka, which I wore inside the sleeping bag.

SYNTHETIC: I've used lightweight synthetic garments (Primaloft & others) from mainly Patagonia and Marmot which have served me well in conjunction with the down bags. In addition to vests & jackets, I also carry a set of poly under garments, either light, medium or expedition, depending on the conditional requirements of the occasion.

So, I've always been well covered (a pun, I suppose) using down & synthetics together. But now, I am curious about the added benefit of hydrophobic down. Again, in theory, sounds great.

Have you had experience using "hydrophobic" down and if so, how did it work for you, in relation to your experiences without it ?

thanks

I'm waiting for Western Mountaineering to decide:



It's highly unlikely that, even if WM makes the switch, I would replace my current WM Ultralite. It's only 11 years old, relatively new by down bag standards. I expect it to last as long as I will, if not longer!

Hi Charles,

Just preliminary feedback from a week with a Big Agnes Pitchpine UL45, which has "DownTek" water-repellant treatment on its 850-rated fill. Wasn't in soggy conditions so don't know how it would fare if not allowed to dry from day to day. I can say there was no clumping or apparent moisture buildup during a week in the Lasen backcountry, but only the first night were we threatened by the weather. We did sleep by lakes every night where condensation could be heavy when we were sans wind. Left the fly off the tent anyway, to catch the night skies.

In sum, a cautious endorsement acknowledging I didn't press the technology in a meaningful way. It doesn't seem to affect loft, as the down's rating seems borne out by the quick recovery when pulled from a stuffsack.

Contra that I've had enough soggy down kit to appreciate the technology's promise.

Cheers,

I would think anything added onto the down would increase the weight a bit. Any change in the ability of down to float around in air may impact its fluffiness. So my question is:
does the exact same weight of fill, one with and one without the coating, make the exact same loft?

Obviously if you use down continuously in cold-wet-humid conditions, any extra weight or loss of loft would be insignificant relative to the advantage of having the down stay dry.

On the other hand, in many conditions (for example, the Sierra) I never had weeks-long cold-damp conditions. You do have to be careful - for example not fall into a creek. But on the whole, I have never had a problem keeping my down dry.

The comparison I would like to see is the best synthetic vs the hydrophobic down.

As for longevity, if it is like my experience with the water-repellants coatings, it would seem that the waterproofing would break down over time - repeated stuffing.


Like OM, I am waiting on more longevity information. I am sticking with what I have right now.

I may not be as experienced as you even though I have been hiking off and on in Washington and Alaska some. I have always had down sleeping bags since I was and Explorer Scout and they have never gotten so wet that they failed to keep me warm. Now I have a bag (two actually) with a highly H20 resistant cover and feel really comfortable with it. So I will not switch to Hydrophobic Down. I have seen water bead up on my new bags and i simply brushed it off. Also, perhaps an aside: I have slept in heavy rain in a Gortex Bivy sack (Moonstone) with out getting even damp inside. Again, water rolled off, never wetting-out the bivy sack.

Hi Jim. For me, at least, the thing that makes this topic interesting isn't a concern about water coming through the tent or otherwise dripping/pouring into the sleeping bag down from the outside. It is, rather, the combination of humidity and of the moisture given off by the body during sleep. That, combined with multiple day trips.

For an overnight or "couple of nights" trip, loss of loft isn't generally a concern. But hike in conditions where it's very humid out and no matter how good your DWR treatment, the down in the bag can get ever more damp each day with a concomitant loss of loft --- and thus warmth. Barring a fortunate break in the weather, the only way to re-loft the bag at that point is to go home and dry out!

This is IMO an even bigger topic the colder the conditions. I've (happily) never used a vapor barrier liner in a sleeping bag, but that what it's about, because loss of loft is deadly serious stuff in colder winter conditions. So I would think that down that does a better job at retaining loft in moist conditions would be of even more interest for winter/very-cold use.

I guess we each see a new product like this from different perspectives depending on the particular issues we're concerned about. An adequate seam sealed tent and/or DWR on sleeping bag and/or decent light drybag to carry it in --- these have never been significant issues for me at least.

I've had the mountain hardware ghost whisperer for a while. It's 800 fill down with Qshield (their brand of waterproofing) and it works pretty well. It's not waterproof, but I would say it's water resistant.
If you're talking about a light drizzle or snow or a quick, accidental, submersion, I think having a shell with a tight weave is more important than the treated down.
I think I speak for everyone when I say that using a wet bag, quilt or jacket of ANY material is miserable.
Hope this helps. Cheers!