A good alternative to WPB gear for ACTIVE backpacking

[Stumphges]

Mike,

I think I’ve seen some pieces on Amazon and ebay. But shipping by Royal Mail is reasonable and UK retailers drop the VAT when shipping to the States, so total price is reasonable to import. I’ve had good times with foothills.uk.com

FYI, the Ostro is a slim fit piece. It’s comparable in size and cut to the Alpine Start, and layers well under it. Paramo call it “athletic fit,” but like the Alpine Start it’s a bit tight in the chest and shoulders compared to, say, the traditional Arcteryx fit.

I mean to do a bit more testing in the shower to get a sense for how much water the Ostro Fleece takes on. It’s extremely water resistant for what it is (>300mm HH) but the DWR is overwhelmed by pressure, as you can see above. It wet out to about the same degree as the Squamish did, but because of it’s furry surface, a lot more water is held by the surface than a smooth windshirt. I suppose it is rather like animal fur, which is also highly water resistant and pumps water from skin outwards but can be flattened and saturated by heavy rain. Of course, the animal inside it can shake it dry and fluff the fibers in the process. We cant do that, so the Paramo system relies on the windshirt outer to deflect most of the moisture from the hydrophobic fur underneath. On the other hand, the Ostro is far denser and has a much, much higher hydrostatic head than the traditional Paramo “pump liner.” I expect it to be as worthy as the Alpine Start in light rain, on it’s own, and might prove very showerproof with the Alpine Start over the top (the combination should come in somewhere around 25-30 CFM, with two layers of >300mm HH) and rainproof with a higher HH windhirt like the designed-for-it Ostro Windproof.

The weight is high, but I’m happy to try it on some trips. The silence is a big deal for me. I really dislike the swish-swish of nylons when in the woods.

[Mike M]

Thanks!  I’m not overly concerned with the weight- thinking it might be nice piece for elk hunting :)

Good to know on sizing, I’m almost always a Large, but had to get an XL with the Alpine Start

[Roger Caffin]

Personally, as a physicist, I find the marketing term ‘waterproof/breathable’ to be a contradiction in terms.
Jackets either leak or get lots of condensation.
So I use a poncho over the top instead.

Cheers

[Mike M]

Roger – I don’t think anyone would argue with that; the best we can hope for (at this juncture anyways) is pretty breathable and fairly water resistant; if you want waterproof you’re not going to get breathable, ditto in reverse

[Stumphges]

Roger, Mike, what about the Columbia EX Featherweight that Richard has analyzed? Based on his analysis, it appears to me that we have a viable WPB option for hiking/backpacking at and below 4 METS with that jacket. For higher intensity hiking we have Roger’s ponchos (and similar designs) and the Buffalo/Paramo/PCU, wet/damp but warm, styles discussed in this thread.

Mike, yeah I was thinking of hunting with the Ostro as well. It could be very good for stalking, particularly if concerned with sound made by brushing against foliage. The Gray Marl color is rather light, and the one I have. They also have a Steel Marl that looks to be a darker shade of gray. I’m going to test the Gray one for UV reflectance this weekend and will post results. I wouldn’t think Paramo would put UV brighteners in their dyes, but…

[Brett Peugh]

So would you say the Ostro is comparable to a R2 (if a hooded version existed) that maybe had been treated with a Nikwax waterproofing wash?

[Stumphges]

Hi Brett,

No, not at all. It might be equivalent in warmth to a Thermal/Expedition weight capilene. So less warm than 100 wt fleece. They call it a fleece but the material is quite dense, with a tightly woven inner layer that opens up on the outside into a short furry face. The fur is not whispy, though, and Roger noted that it’s quite durable and snag-resistant in his forum review of the Bentu fleece (which appears of the same fabric).

The Ostro Plus Fleece is more similar to the R2 (Polartec Thermal Pro), or at least the front and back sides are.

Whether you could turn R2 fleece into a pumping layer akin to Paramo by treating with Nikwax is debatable. Thermal Pro with furry faces appear like they would work that way, but I’ve never tried it. I think it would depend on whether the polyester has been chemically or mechanically treated to be hydrophilic.

I recently bought a 100wt fleece pullover at a Columbia outlet that has a furry face and smooth inner surface. I thought, hmmm, and treated it with Nikwax. I can now pool about 1/2 cup of water and it won’t soak in and it beads water nicely in drizzling rain. Because it lacks a very tightly woven inner face its hydrostatic head is very low and wouldn’t resist much more than a drizzle, but it is still kind of cool.

It’s interesting to see hydrophobic fleeces in action. This is a video by the inventor of the GTI PFC-free DWR used in Marmots newer WPB jackets and that will be used in BD’s Distance Windhsell in 2019: https://www.youtube.com/watch?v=tDvZlOCiZ04&frags=pl%2Cwn

[Brett Peugh]

So the regular Ostro would probably more akin to a Mountain Hardwear Microchill Lite full zip hoody with it being furry/fuzzy on the outside and a smooth tight woven structure on the inside.  That or the R2 is what I have been using with what I think is a Gen II Level 4 windshirt and they seem to work very well.  I have not used Nikwax on them but have thought about it.   I also have not done the shower test but will try to in the next few weeks.

[Stumphges]

Brett,

Don’t put Nikwax on anything that will have regular contact with an Epic silicone-encapsulated garment. In another thread Roger informed us that wax will foul the hydrophobicity of the silicone coating. With Epic we’re stuck with hydrophilic wicking underlayers. This might not matter, as R. Nisley expressed the opinion  upthread that whether the underlayer in this type of system works by capillary action or capillary depression doesn’t really matter. I have my doubts, personally, as it seems to make intuitive sense that having a hydrophobic surface to greet any mist that makes it through the outer layer would be helpful to the goal of keeping water nearer the surface of the layers.

I know that an academic at Leeds University wrote a paper, maybe a dissertation, that included a comparison of Buffalo (hydrophilic wicking inner layers) and Paramo (hydrophobic “pumping” inner layers), but I haven’t been able to find a copy of it.

Anyone got it? Richard?

[Brett Peugh]

Okay, thanks, I will keep using it the same way I have been then.

[Stumphges]

Mike,

Sorry for the delay in this follow up on the Paramo Ostro. I used Atsko’s UV reflectance kit (a small black light at a particular frequency.) The Ostro has some small isolated fibers that are highly reflective of UV light. The bulk of the fabric is not, but based on the info Atsko has on their website about animal vision and UV light, I think the Ostro might look to an animal that it’s got some glitter sprinkled on it.

[Mike M]

^ that’s certainly interesting- thanks

[Stumphges]

Like some others that have posted to this thread, I’ve experienced getting pretty soaked using this method, particularly when using a very permeable wind layer like the Alpine Start. Basically, I’ve found that the military Epic layers have much greater functional water resistance than conventional DWR fabrics that show >300mm HH. But as long as one knows when to put a shell on and slow down lest the active system get completely overwhelmed, it’s OK.

In any case, I often arrive at camp pretty damp and am looking for a camp jacket with sufficient warmth and air permeability to allow my active layers to dry out some before bed. I’ve avoided synthetic belay jackets for a long time due to loft degradation but am taking another look given my need for something that will keep me thermo-neutral down to freezing over the top of damp/wet active layers. It seems I’ve got two good options:

1. One of the lightly shelled Alpha Direct with heavier weight lining (e.g. 120 g/m^2) These seem like lighter weight versions of a Buffalo Shirt and seem like they might work for static use when wet.
2. A Patagonia Nano or Arcteryx Coreloft piece (aka Climashield). Both have highly permeable outer layers and are meant as active insulation, but seem that they would work for this static use as well.

Has anyone tried this type of approach? Any better ideas?

[Mike M]

might be worth looking at the Nano Air as well, very permeable- not a lot of insulation, so not sure how it would be at freezing static over damp layers, you might need more???

here’s what Dave C has to say about it

 

https://bedrockandparadox.com/2017/09/22/patagonia-nano-air-light-hoody-the-fleece-killer/

[Stumphges]

Thanks Mike. I think you’re right about needing more. Took the time to crunch the numbers with R. Nisley’s data and it looks like both the Nano Air and the heavier weight (120g) Alpha Direct would come up a bit short, offering camp  chore thermo-neutral of only around 50 F over the top of hiking ensemble.

[Mike M]

Yeah I think most of the “active insulation” jackets will probably come up short, but a heavier synthetic w/ a decent breathable fabric should do the trick.  I’ve found Apex to be pretty good syn when it comes to moisture, also resists compression wear better than most syns.

Nunatak offers a couple of Apex jackets that might be worth looking at, offered in different insulation thicknesses and they also offer a variety of fabrics- might find one that fills the bill.

[Stumphges]

Just realized that Enlightened Equipment offer their Torrid Climashield hoody in an optional 7d fabric with 35 CFM air permeability. 2.0 oz Climashield would be borderline for around freezing but 35CFM would work great for this purpose. If the wind picked up in camp a shell over the top with the vents open…

They also offer their Copperfield windshirt in the 7d 35CFM fabric, which might be of interest to some following this thread. (No mention of HH on their site.)

[Stumphges]

Black Diamond have started selling their 98 g Distance Wind Shell with GTI “permanent” fluorocarbon-free DWR. Black Diamond are marketing this for adventure racing and high output pursuits and touting its breathability, so the CFM might be in the useful range for this ACTIVE precip strategy. Of course, even if so, the HH will be the key – luckily we are supplied with the two cup test to ballpark that.

We’ve seen “permanent” DWRs before – Rab recently made this claim about a windshirt – that turned out to be bogus (they just lasted a little longer than typical, it turned out.) GTI has lots of Bundesmann videos on Youtube but I don’t know enough to use the data provided (many of the videos end with ISO 9865 data tables) to evaluate BD’s claim.

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