Hydrophobic Down - Any Disadvantages?

[Richard G]

Planning on ordering a new sleeping bag, and going for the hydrophobic down version.

Any disadvantages I should be aware of, or is it pretty much better than non hydrophobic all round?

[ZeroDarkBivi]

Top Down manufacturers Arcteryx and PHD don't use hydrophobic down.

I can't remember the full explanation, but I think some of it was based upon a lack of evidence of long term durability.

[Wotsits]

I can't remember the full explanation, but I think some of it was based upon a lack of evidence of long term durability.

Spoke with a manufacturer about this^ a while ago. They said that they ‘thought’ the hydrophobic treatment ‘may’ cause the down to become less tolerant of being packed/unpacked..

If they’re correct You’d have you make your decision on whether you’d prioritise water resistance over longevity..

[Richard G]

Given I only use my bags about 5x a year max I doubt that's going to be a concern.

I store them hanging up too, so no compression there either.

[Alpinum]

Given I only use my bags about 5x a year max I doubt that's going to be a concern.

I store them hanging up too, so no compression there either.

Go for it. My most used winterbag (custom Cumulus with 630 g 850 cuin down) and medium weight down jacket (Berghaus Ramche, preproduction Gen 2) are both hydrophobic down and it does make a major difference when I sleep out for multiple nights. Mostly you can watch how the bag looses loft night for night. Here, the only thing that happens is the bag puts on some weight. For multiple weeks I still go with a VBL obviously, but up to about 5 nights I go without.

Of both items I have this feeling, that their as high performing as such gear gets at the moment.

There are different way to treat down to make it hydrophobic. Having experience in the lab with modifying surfaces by plasma treatment, I'd go down that lane rather than the washed in treatments (as used by most) but then, gear isn't just about the down itself is it...

I mostly wash my quilts/bags after about 100 - 150 nights, but always use a 7D liner to keep muck out.
If I look into what washing down with the right soap does it's a no-brainer anyway.

They said that they ‘thought’ the hydrophobic treatment ‘may’ cause the down to become less tolerant of being packed/unpacked..

I wonder if they have any clue of the chemical reactions by var. treatments on the structure of down, which, after all, is just a bloody protein (b-sheet). Having met var. manufacturers at outdoor shows, I got the impression most have no clue of the details and thus no full, not even half an understanding if any at all, also very little research is done (also in fabrics) considering the size of the market.
I wonder how many outdoor manufacturers have biochemists or experts in proteomics employed.

Anybody here can speculate on this specific topic just as they like and it'll be likely of same value as what the manufacturers say. My estimation. And speculation.

[Richard G]

I don't think I'll be alive long enough to get 150 nights out of a bag.

[fatbikephil]

On a related note, any tried using the nikwax down treatment on a non-hydrophobic down bag or jacket? I bought a bottle of it last year but so far haven't dared use it...

[Alpinum]

On a related note, any tried using the nikwax down treatment on a non-hydrophobic down bag or jacket? I bought a bottle of it last year but so far haven't dared use it...

Do you mean Nikwax Down Proof?
Sounds interesting.

Damnit, we just washed two down items without knowing about the Down Proof. Would've liked to give it a try.

I don't think I'll be alive long enough to get 150 nights out of a bag.

You should sleep outdoors more

[Richard G]

Managing to do it once might be a neat trick. Though I have managed a few hours after significant alcohol... but sadly not without.

[PaulB]

It was nikwax downproof and other coating products that started the damp resistance trend. Plus, it was the product that highlighted the issue with the down tendrils breaking off and folk ending with a bag of none lofting down bits. Experiments took place at ME Glossop and is probably why Pete doesnt use treated down at PHD. The none treated down out of the same batches were fine. Obviously this took place quite some years ago and modern chemicals will have probably changed.

I do have a Rab Exped 1500 bag that has down out of my old ME Redline that I overwintered with in Spitzbergen in the 80's. When the down was transfered, they found it performed as well as the top end down then (late90's) in terms of weight:volume. It still holds it own now 35yrs on.

Apologies for going OT.

[benp1]

I only have one hydrophobic down product, an EE quilt

I have to say it’s nice knowing that I can get a bit damp without too much worry. In reality I’m rarely out for more than 2 nights at a time so damp build up isn’t a killer.

I had bivied in the alps a few weeks back without a tarp. It rained for a bit and my bag got wet, my winter non-hydrophobic down bag. It’s survived but it would have been preferable to have had my EE quilt for it (plus I was hoping it would be colder at 2,600m next to a glacier)

[fatbikephil]

On a related note, any tried using the nikwax down treatment on a non-hydrophobic down bag or jacket? I bought a bottle of it last year but so far haven't dared use it...

Do you mean Nikwax Down Proof?
Sounds interesting.

Damnit, we just washed two down items without knowing about the Down Proof. Would've liked to give it a try.

I don't think I'll be alive long enough to get 150 nights out of a bag.

You should sleep outdoors more

Yup that's the stuff - seems to suggest its only good for 2 season or less bags / jackets. My bag could do with a wash so I might give it a whirl thereafter...