Zpacks Octa Fleece Hoody Review
The Zpacks Octa Fleece Hoody is an ultralight hoody made with Octa polyester fiber. Made by a Japanese company called TEIJIN, Octa fibers have a hollow core surrounded by eight projections aligned in a radial pattern that looks like a toothed gear. When woven together to create fleece, they create an ultralight, highly porous, quick-drying, non-see-through fabric that insulates by trapping warm air. The result is a fleece fabric that is warmer than conventional fleece but weighs up to a third as much. Functionally, Octa garments are similar to Polartec Alpha Direct fleece, which is the darling of many ultralight backpackers because hoodies made with it are also exceptionally lightweight and warm.
- Gender: Unisex
- Weight: 5.3 oz in a size large
- Zipper: 1/2 length
- Pockets: 1 (kangaroo style)
- Hood: Under helmet
- Thumb loops: yes
- Material: 80 GSM Octa Fleece
- Color: Black with blue trim
- Sizing: Runs small (size up)
The Zpacks Octa Fleece Hoody is made with 80 GSM (grams per square meter) Octa fleece fabric that is fuzzy on the inside with an abrasion-resistant mesh exterior. TEIJIN manufactures Octa fleece fabric in a number of different weights, ranging from 67 GSM – 220 GSM, with different finishes (scroll to the bottom), so you need to pay close attention to product specs when shopping for Octa garments or comparing them. Numerous other companies have also started making Octa fleece garments in multiple weights, including Norrona, Arcteryx, and Mountain Hardwear, amongst others, and it is worth surveying the field to see what’s out there.
The Zpacks Octa Fleece Hoody has a 1/2 length front zipper, thumb loops, and a kangaroo pocket in front, which is situated high enough that you can put your hands inside while wearing a backpack hipbelt (provided you’re not gripping trekking poles). While the hood is not adjustable, it is human-sized and fits nicely under a climbing helmet. The thumb loops provide extra insulation around the wrists when worn and prevent the sleeves from riding up when you put on a jacket.
Since the fleece is highly porous, the Octa Fleece Hoody must be worn with a windbreaker or hardshell in cooler weather, especially if it’s windy. I’ve stayed comfortable down to freezing (30 degrees F) when wearing a medium-weight LS baselayer shirt and an Enlightened Equipment Copperfield Windbreaker over the hoody as long as I’m hiking vigorously and generating body heat. But as soon as I stop, I have to layer up to stay warm. That’s the same case with my Polartec Alpha Direct 90 GSM hoodies.
So what are the biggest benefits of the Octa Fleece Hoody over comparable Polartec Alpha Direct hoodies? One of the first things I tested was the Octa’s Hoody’s reactivity to velcro (hook and loop), which is widely used in outdoor gear but latches onto and tears at fuzzy Polartec Aphla fabric. Much to my surprise, the velcro has no impact on the fuzzy interior fabric of the Octa Fleece Hoody. While it does adhere slightly to the garment’s external mesh, it peels off easily without disturbing the fibers. I suspect this is due to the shape of the fibers used to make Octa fleece and is indicative of the enhanced durability of the fabric. Time will tell if this is the case, but I have a strong intuition that that’s the key difference between the two.
The other big difference, at least on this Octa hoody build, is the smooth exterior, which is much less prone to abrasion or getting caught in vegetation. Polartec Alpha Direct is a very gauzy, porous, and delicate material, both inside and out, that can easily snag and requires some care to “keep safe.” It was never intended for external use but was meant to be used as insulation inside an outer shell layer. That’s not the case with Octa, which has a more durable external surface engineered for that use.
Recommendation
The Zpacks Octa Fleece Hoody is an ultralight hooded garment made with Octa polyester fleece, which is much lighter weight than conventional fleece garments. It has a rich feature set, including a 1/2 length zipper, thumb loops, and a kangaroo pocket that make it suitable for three-season hiking and backpacking as an outer layer in warmer weather or as mid-layer insulation with a windbreaker or hardshell in cool or windy conditions. If you’re looking for a way to reduce the weight of your hiking clothes, the 5.3 oz Octa Fleece Hoody can provide the same warmth as conventional lightweight fleece hoody (100-150 GSM) but only weighs half to a third as much! That’s an incredible bargain, considering the high cost of ultralight backpacking gear today.
Disclosure: Zpacks donated a garment for review.
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How does the Octa do with moisture absorption? One of my favorite things about Alpha Direct is that it holds onto almost no moisture. For example, when taking it out of the washing machine it’s virtually dry from the spin cycle. When hiking it in with a windshirt and sweating, I can just continue to wear it at the end of the day for 10-15 minutes and it will be dry. AD is almost like a Brynje Superthermo in a fleece form. Does Octa perform similarly or does it hold onto more moisture like a a traditional grid fleece would?
It holds very little moisture – it’s polyester. A traditional fleece hoody weighs 3-4 times as much and is a 160 gsm fabric. That’s why these ultralight fleeces are so different.
I have a Mountain Hardwear 1/4 zip Octa fleece (can’t remember the name). It’s an absolute sponge when wet. When dry, it’s fantastic. I’m wearing it today for a snow hike, in fact. Maybe I’ll weigh it tonight, dry and wet, but not sure it matters. The weight is at least 2-3x when wet. A lot. While I appreciate the durability and slight wind resistance compared to Polartec Alpha, I’ll take my Senchi in the summer (or desert), every time, because even though it has almost no wind resistance it holds less water.
I like a more wind-resistant fleece for winter so I can hike without a wind shirt or shell if I’m too warm. Why would you bother wearing your MH Octa fleece when you know that something else would be better?
I’m actually really pleased with the MH Octa in winter under a light and breathable jacket (Patagonia Nanoair Hoody). Works for alpine mountaineering and snowshoeing in Colorado extremely well. When needed I will put a Black Diamond Alpine Start wind shell over the Nano Air, or an Arcteryx Beta SV if it’s really brutal. (And I may change the Nano Air for a Rab down jacket based on weather forecast and route.) Under the Octa is either a merino t-shirt or various weight long sleeve shirts depending on forecast. I’m good to -30F (with appropriate gloves/mittens, hat, glasses/goggles) as long as I’m moving so I’m not looking to change this up. The Octa is a great piece, not constricting and plenty warm and breathable in this system. But not in rain. That was my original point however I felt compelled to answer your more general question. Hope this helps. Note: I run warm and I try hard to avoid sweat moisture in winter.
Ah. Ok.
How would you compare warmth of similar weights ( is 90 gsm octa yarn more or less warm than 90 gsm alpha)?
Indistinguishable.
I like Octa smooth face fabric that makes it easy to pull fleece garments on and off over it vs Alpha. What’s really nice about the ZPack hoodie vs the Mountain Hardware and Arcteryx, is that ZPack has a neck zip on their hoodie for added ventilation. Unfortunately at this time ZPack is sold out!
well other People make octa garments too. We cite a few above.
Serious question: Do you find the added ventilation really all that useful? I have the MH Airmesh and just walking through my house I can fell a noticeable breeze , I can’t imagine needing more ventilation with octane, granted I haven’t used mine much as an actual “active” layer.
Airmesh is made with Octa fibers, so I’m not following you completely. Do I find the added ventilation useful? Why yes. Because any porous baselayer will move moisture away from the skin and into a midlayer faster. Take your pick – airmesh (which is worn as a baselayer), bryjne (synthetic or wool) etc. I judge most baselayers on their porosity, which also helps trap warm air. But I rely on my mid-layers for warmth. To add – this zpacks hoody is a midlayer garment not a base layer and also not really very good for winter weather use because its not warm enough.
Another tip. If going with friends, make sure everyone is using the same fuel stove combination so you have some redundancy.
My comment was directed at BMCF, they stated they liked the zipper on the zpacks for added ventalation, I just thought the airmesh was already incredibly breathable as is, what does the zipper really add?
Doing an 11K pass in Sierras in early morning I will have on base layer, Octa or Alpha fleece and wind jacket, those passes are above tree line and very cold and windy in early morning. But the steep climb will have you cranking out a lot of heat, so you zip down the neck of fleece and wind jacket the amount you need to dump heat. At top zip both back up. Also, you can fine tune better having the zip rather than without, and they have a nice long zipper on the ZPack Octa. Cannot imagine not having a zip neck on any fleece garment.
I love Octa. My favorite cool-weather shirt is a MH Airmesh Half-Zip. It is unfortunate that they stopped making it with the zipper because I do use it frequently to vent heat (and, yes, it is useful for that). The MH looks nice, too, which is a bonus.
This Z-Packs hoody is the next best thing, but I don’t need the hood or pockets on my shirt. They downgrade both appearance and utility, at least for me. Still, I don’t see anything better as of this writing.
I wear Octa next to skin (or over a Brynje). AD90 (with full zipper) is a great mid-layer on top of it.
My POV: Octa > AD60. AD90 is about right for a mid-layer. AD120 for a heavy mid-layer for below -5C/20F.
Hey Philip. Thanks for another comprehensive review. This fleece seems excellent. One question: how does it perform when wet? In your Alpha Direct fleece review, you mentioned that it isn’t warm when wet. Is it different for Octa? This point is crucial because many of my hikes are in wet climates where I’m wet from rain/perspiration. If it retains its warmth to a high degree when wet, this fleece seems perfect for me.
Thanks!
I performs similarly to Alpha when wet. If you fill in the holes with liquid, they can’t hold air. Get a thicker fleece like an Patagonia R2 or even an R1.
Hi Philip,
In your experience, does forest debris (like pine needles) get stuck in the mesh of Octa (like it does in 3D mesh back panels on backpacks)? Thanks!
I haven’t rolled on the ground in one. I doubt it though.
Since it’s polyester , how does it handle funk? How long til it stinks? Serious question