Field Tested: Arc’teryx Alpha SV CZ Bib

Gore-Tex bibs are a rather specialized piece of clothing. Hardshell pants are pretty serious gear already, and when you add a chest-high bib to the ensemble, you end up with one very hardcore pair of pants. So when Arc’teryx sent me a pair of their redesigned Alpha SV CZ Bib pants for review, I wasn’t quite sure how and where to fully test them. As it turns out, however, these Bibs are one seriously nice — if a bit overkill — pant for your everyday climbing needs as well.

I had my qualms about using these pants, having not used, let alone owned, a waterproof-breathable pant since 2001, back when I had a pair of some kind of Gore-Tex XCR pants that I used during a 5-month trip to Europe. They were waterproof, yes, but I’m not entirely sure about the breathable part. I’m pretty sure I could’ve worn plastic bags over my legs and gotten much the same performance.

A dozen years have passed since then, and everything I’ve been reading assures me that the latest waterproof-breathables are significantly more breathable. Naturally, it was time to test this claim so I wore the Bibs in a wide range of temperatures, from -25C to +5C. Waterproof? Definitely. More breathable than my old hardshells? Absolutely. Breathable enough to use on a regular basis? Surprisingly, yes!

Constructed of the latest Gore-Tex Pro, the breathability of the membrane/fabric blows me away. It is closer to a heavy-weight softshell than a waterproof hardshell, and I don’t hesitate to use them in lieu of my typical softshell pant setup. Venting is superb thanks to 3/4 length side zippers (3/4 length on a bib = pretty much the whole length of my legs) with dual sliders (so you can open up the leg from the top or the bottom). Providing additional venting, if needed, is the Crotch Zipper (the CZ in the bibs’ name) with three sliders so you can open up a vent at the front and the back of the pants simultaneously (or just unzip the whole thing, chap-style, though your climbing partner may give you some odd looks). Obviously, the CZ also comes in very handy for bathroom breaks, especially when wearing a harness.

TheAlpineStart_Arcteryx_Alpha_SV_Bib_CZ_fullThe size-Medium on my 180cm-75kg frame are an excellent fit. 

The knees and seat are of a higher-denier Gore-Tex Pro for durability, while the very top of the bibs is Arc’teryx’s own Fortius 1.0 softshell material, super-stretchy and very breathable. There are two zippered chest pockets at the front and a waistband drawcord to snug the pants around your hips. Minimalist and comfy (even under pack straps) suspenders hold up the whole thing. All the zippers are of the water-resistant variety, and seem to do their job well.

There is a very large crampon/ski edge patch on the inside of each leg, and the cuffs have a stretch drawcord, a snap at the opening and even two riveted holes to use as tie-downs. In addition to this, there’s a removable elastic strap — LegWrap in Arcteryx-speak — at around mid-calf height to cinch the pants closer to your leg, which helps to both minimize crampon snags and prevents the pant legs from twisting around while hiking or scumming up a chimney. This works as advertised, weighs next to nothing and takes up no space. Taken all together, that’s a lot of features and attachment options packed into a small space!

TheAlpineStart_Arcteryx_Alpha_SV_Bib_CZ_pant_legThe ‘LegWrap’ clips around your calf, keeping the pant leg from rotating around. Numerous attachment options ensure the pants will stay put over any boot imaginable.

I’ve really enjoyed using and wearing the Alpha Bibs. Fit is superb, with excellent articulation thanks to clever patterning, and I haven’t had any issues with the pants riding up, down, or sideways, over the course of a day’s climbing. The bib style calls for a slight rethink of typical layering, and I’ve found myself wearing less or thinner layers on my upper while simultaneously adding warmer layers over my legs (Gore-Tex doesn’t provide much insulation value in comparison to most softshell materials). However, as mentioned above, even with warmer layers heat is easy to dump thanks to the large side zippers.

The high back ensures there are no drafts or cold spots (which is soo nice!!), and the two massive pockets up front provide useful extra storage space (and are big enough to fit a midweight pair of gloves each). I was initially concerned that my harness would slide around over the slick outer surface but those fears proved unfounded. The various straps and elastic cords at the lower leg keep the pants tucked close and alleviate any worry of snagging an errant crampon.

TheAlpineStart_Arcteryx_Alpha_SV_Rainbow_Serpent_2Seconding the first pitch of Rainbow Serpent in The Ghost.

With so much protection on offer, I felt silly using these for (just) ice and mixed climbing around the Rockies. They feel destined for sketchy traverses high up in the Himalayas, soaking-wet rime in Patagonia or windy ridges in Alaska. Or some other extreme environment: take your pick. Personally, I can’t wait for spring alpine season!

The Alpha Bibs weigh 571 grams in a size Medium, not much more than my typical softshells (Arc’teryx Gamma AR at 519gms), while providing much more coverage, wind protection and absolute waterproofness. Of course, there is a significant price difference — $650 for the Alpha Bibs, $200 or so for typical Arcteryx softshell pants — but if you need maximum durability and protection from the elements, the Alpha SV CZ Bib is the obvious choice.

Pros: great fit, bombproof protection, excellent venting
Cons: expensive
Overall: If you’re heading on an expedition, or planning to climb something more akin to a water-fall than to waterfall ice, this is the pant of choice. They work very well as an everyday climbing pant but it just sometimes feels downright silly using something so robust in such mellow conditions.

One thought on “Field Tested: Arc’teryx Alpha SV CZ Bib

  1. jon walsh says:

    But when in nasty conditions, especially high winds or high humidity situations, whether it’s slashing rain on the approach, wet snow, or water from a high volume waterfall, ski-touring on a storm day or even just getting outside on a storm day, there’s nothing better! Those bibs have made it possible for me to climb many memorable routes! And, they absolutely rule for powder skiing – in B.C. at least 😉

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