GSMNP PHGT, Part 1: ZPacks 20F Sleeping Bag

I am going in a bit of a different direction than I normally do with this Post Hike Gear Talk (PHGT) post. Typically I post once and discuss a number of items I carried on a given hike, however, many of those items are often times mentioned in my PHGT entries (or have their own post elsewhere own my blog). Now that doesn’t mean that those items don’t deserve continued discussion, but there are a few items I wanted to highlight from this hike that I have not mentioned much, or even at all, so I decided to break this PHGT entry up into 3 separate parts. I felt that each of these 3 items deserved their own post so that they didn’t get lost in the sea of all the other items. And since my most recent hike was a colder than normal hike, I wanted to focus on a few items that I relied on to actually keep me warm. So, part 1 of this PHGT series will be covering my ZPacks 20F Sleeping bag.

I bought the ZPacks sleeping bag in the spring of 2016, but due to timing and warmer weather I didn’t have any opportunities to use it until a couple of months ago. It’s also worth noting that my particular bag is the previous version of their sleeping bags, which was constructed with all horizontal baffles. They have since redesigned these bag’s so that they now use a combination of both horizontal and vertical baffles. As well, the names of the sizes have been changed, but actual specs and dimensions, fill weights and total weights have remained the same. I will make note of it below when necessary.

At this point, I have only used my ZPacks sleeping bag a total of 6 nights on the trail (4 in October and 2 in November). Other than that, like any gear nut, I must admit that I have laid around in it at home extensively… lol! I do understand that many would still consider this to basically be no use at all, and trust me, I do wish it were more, but I feel that I have used it enough to provide some feedback on how I feel about this sleeping bag, and how it has worked thus far with the rest of my gear (I prefer to look at my gear as part of a system, and not just on its own).


ZPacks offers a number of options on their website to configure one of their sleeping bags so that it is the best fit you and your needs. For me, I decided to start with the 20F version, and then decided to go with the long and wide version (now called the “standard” width). I chose not to add a draft tube, and opted to go with the standard 3/4 length zipper option. On a less serious note, I chose to go with blue because I thought it looked good… although, the green does too! At the time of my purchase (and even now at the time of this writing) their stock down is untreated 900 goose down fill, which is “ethically sourced straight from the producer.” (It is also worth noting that the ZPacks site does not have an option for extra fill to be added to their bags as each baffle is already 30% overfilled. If you feel you need a slightly warmer bag it makes more sense to go with the next warmest rated bag.)

To begin with, I gotta say that I am quite happy with the way my ZPacks sleeping bag fits around me (or maybe, I in it). I am 5’10” tall (when standing) and when I lie flat on my back, without shoving my feet into the foot box to the point of compressing the down, the top of the (un-cinched) sleeping bag hits me around my lips, or just under my nose. When I cinch the top down, it sits comfortably on my shoulders and still does not force my feet into the foot box to the point of compressing the down, although, there is very little room for play in length when cinched down. Based on this, I would say it fits me as it should. By this, I mean it is not to short to compress any down, and just long enough to fit me without being to long. This scenario is optimal in that it is the most thermally efficient method of sizing a sleeping bag.

As for the width, in my opinion, it’s another home run! I am currently 184 lbs. When I measure the circumference of my chest and shoulders with a tape I am about 50.5″ (when standing). As I mentioned, I opted for the wide version, which ZPacks lists as 61″ wide and this is perfect for me (again note, this width is now called the “standard” width). I could likely fit in the slim version, but I imagine that when one lies down, they tend to relax and spread out at least a little more (which is why I note my measurements as “standing”). When I lie inside my bag (when completely zipped up) the bag wraps loosely around me with just enough room for me to comfortably wear a puffy if needed and still not compress any insulation. As well, I find the taper of the bag to complement my body shape quite well. From the head to the foot, the bag fits me about the same: not too tight, but still loose enough to move around freely in, or layer slightly thicker pieces to complement the bags temperature rating. This sleeping bag fits me very comfortably without being to tight to be uncomfortable, or so loose that it negatively impacts thermal efficiencies.

A few online discussions I have seen about the ZPacks sleeping bag have seemed to gravitate towards the shape of the foot box. ZPacks has chosen to go with a simple envelope-shaped foot box, which I would imagine results in a less complicated construction technique, and probably less wasted materials. I would also assume that this design would allow the staff to produce these sleeping bags easier (faster) and at a little less cost. Some of the other sleeping bag manufacturers use a 3D, trapezoidal, or anatomically designed foot box which is essentially shaped to match the shape of your feet when relaxed. There are advantages to each, however, in light of the fact that ZPacks is a company that focuses on lightweight and simple, yet effective pieces of kit, I think the envelope shaped foot box suits their goal more.


In my experiences, I have found no issues or faults with the envelope-shaped foot box when it comes to actual use. Sure, if I think about it, it feels a little different than my other sleeping bags, but that doesn’t mean it is less comfortable, or even less warm (which is what actually matters). When lying on my back, my feet don’t actually point straight up, but rather relax and point/drop down a little. Because of this, the envelope shaped design has worked fine, and my feet do not compress the down in the sleeping bag enough to matter, if in fact, at all. But, this is definitely something to think about when deciding on the overall length of the bag. Based on my height (5’10” when standing) I would say that they (may) have already figured some foot drop into the lengths. And as I mentioned above, when my sleeping bag is cinched closed at the shoulders, it is a perfect fit for me lengthwise even with my foot drop. If I were another inch or more taller though, I would say that the X-Long would likely be a more suitable option for me. Another words, at 5’10” I would say the long version is perfect for me.

So, onto some real-world use:

The lowest temperature I have used this bag in was 23F and the highest has been in the low to mid 40’s. The first 4 nights of use was inside my Hexamid Solo+ Tarp and Hexanet and the outside temps ranged from mid 30’s to mid 40’s. The last 2 nights I used a mesh top bivy, inside the shelters in the GSMNP, and measured temperatures those nights were 31F the first night and 23F the second night. The warmest nights I slept in nothing but my compression shorts (undies) and a t-shirt, and on the cooler nights I slept in a pair of Patagonia Capilene 2 long bottoms and a Capilene 2 long sleeve crew shirt. The last night, which was the coldest (23F), I also used my Patagonia Capilene 4 Extreme Weight Hoody and a wind shirt, as well as a pair of mid weight SmartWool mid length socks and my GooseFeet Gear down socks.

The nights in the low to mid 40’s I definitely had to unzip the zipper and did not cinch the neck area closed. I was not uncomfortably warm in the bag, but at times I got close. Of course the nice thing is that since it has a 3/4 length zipper, it is quite easy to simply throw a leg out to help cool off. However, I would say that for me, the mid 40’s is all I would want to carry this bag in. It’s just too warm for anything more for me.

On the nights that the temps were in the mid to high 30’s I was pretty dang comfortable just by zipping the bag up and leaving the neck open. Once the temps started dropping into the low 30’s though I found myself loosely cinching the neck area closed, and opted to wear my long bottoms and my long sleeve capilene 2 crew shirt. This was a very comfortable set-up all night long!


(Note my buddy Benny’s 10F ZPacks sleeping bag next to mine in the photo above!)

The last night in which I have used the sleeping bag happened to be the coldest, which was 23F. For me, once temps start dipping into the 20’s is when I really start noticing it more. On this particular night I ended up wearing my down socks and a pair of mid weight wool socks, although I didn’t actually pull my down socks on until sometime in the night… likely when the temps started getting closer to the 23F mark, and my body began running out of fuel to keep me warm. I wore my capilene 2 long bottoms all night long and my legs never got hot or cold. Up top I went to bed wearing my capilene 2 long sleeve shirt as well as my capilene 4 hoody. About the same time that I pulled my down socks on that night is when I also slipped my wind jacket on. I used the hood on the cap 4 shirt all night long to cover my head and neck, and once I put the wind jacket on I also used that hood.

I stayed warm all night long, but around 4 am I did begin to feel some cool spots around my torso and my feet when I would move around. Once I put the down socks and the wind jacket on, I did not notice those cool spots any longer. Worth noting here is that I don’t feel like I went to bed with enough to eat, or even hydrated enough. As well, I was in bed by 8 pm. This means 8 hours later, at 4 am, when I began to feel cool, this was likely in part due to the fact that my body was also running out of fuel. Eating and drinking enough is essential to staying warm, and even more so during the colder months since it is common to crawl into bed earlier than normal. When the sun sets at 5 pm it can get cold fast, and a warm “bed” is so nice to crawl into a little earlier than normal, however, this also means the body will need a bit more fuel to stay warm for a longer amount of time at rest. Considering the fact that I was just fine for the first 8 hours though, I think that the sleeping bag actually performed quite well at this temperature.

So sure, at this time I only have 1 night of use in temperatures close to what this sleeping bag is rated for, but that night told me a lot based on my knowledge of my own past sleeping habits and conditions I am generally in. Saying that, I am looking forward to using this sleeping bag more in temps both above, and even a little below the quoted temperature rating (with other pieces of my clothing and gear) to see exactly where it will sit with me. At this point though, I feel like the temperature rating is pretty accurate for me. And for future trips, if I am expecting temps to fall between the high teens to low 40’s, this bag will definitely be in my pack!

Something else I would like to mention is the fact that this is a 3/4 length zippered “sleeping bag.” It is actually something of a hybrid between a sleeping bag and a quilt. It zips up like a sleeping bag, but doesn’t have a hood like a quilt. Honestly, at first I was turned off at this idea. I felt that the zipper was silly to have on a “quilt.” A quilt is supposed to be a featureless sleeping bag, but the ZPacks bag seemed like it was caught in the middle. If I wanted to go light, I went with a quilt, if I wanted features, I went with a sleeping bag. After using the ZPacks sleeping bag though, I must admit that I am actually quite happy with it, and feel like it is actually a smarter option than I first thought.

Speaking of features, I like that the ZPacks sleeping bag does not have a hood since I already have a number of hoods on my clothing, not to mention in colder weather I always bring along my Black Rock Gear down beanie too. The only feature my particular ZPacks sleeping bag actually has is the zipper, which is great because it allows a very easy and simple, yet effective method of blocking out drafts (which is one of the biggest complaints with folks using a quilt). And being that I have always turned inside my sleeping bag, a draft tube along the zipper isn’t necessary for me since it is easy for me to keep the zipper beneath me. (This is one area that a hood on a sleeping bag has been a problem for me though, when I turn inside the bag, the hood is not near as effective since my face ends up in the side of the hood and the side of my head is exposed.) So, for me, the ZPacks sleeping bag is essentially a zippered quilt; or the best of quilts and sleeping bags and nothing else, and let me just say: “It works!”


Before purchasing this sleeping bag, one of my main concerns (next to fit) was how much I would feel the zipper beneath me when lying on top of it. ZPacks has chosen to use a lightweight #3 zipper, which is actually a pretty small zipper when compared to other sleeping bag zippers. It is not stiff and heavy, but I think that for this bag, it is a good choice. Based on the way I get in and out of this bag, I will rarely be zipping and unzipping it, so I don’t feel like it will be too small to stand up to long-term use, but it is small enough so that I don’t notice it when I’m lying on top of it! When wearing very minimal amounts of clothing, such as just a t-shirt, I can feel it somewhat, but not so much that it is bothersome. Of course, when wearing a little more clothing (such as my cap 4 hoody) I can’t even tell the zipper is there. I actually found myself at times sliding my hand beneath me to feel for the zipper… just to make sure it was still in fact beneath me!

ZPacks has also opted to use a 3/4″ center release flat clip to clip the neck of the sleeping bag together. I must admit, this has been more bothersome than the zipper by far, but to be fair, I don’t know of anything else that they could use to make it any better. When the sleeping bag is zipped all the way up and clipped is closed, I can sometimes feel this clip in the back of my neck. Again, this is with minimal or no clothing, and when using a pillow (which for me is all the time). But, if I use the hoods on my clothing, they will actually add enough padding to that area so that I don’t feel it so much. As well, I found that by simply reaching back and pulling the sleeping bag slightly askew one way or another would reposition it out from directly beneath my neck. The only thing I could think to help this situation is if they are to use a longer piece of their binding tape (grosgrain ribbon) to offset the clip so that it wasn’t in the direct center. But, if there was anything I would change about this bag, this would be it.

Also, being that the zipper is on the bottom, getting into and out of the bag was also somewhat of a concern for me… that is until I received the bag. For me, I have found that by just leaving it zipped up and clipped closed, it has been rather easy for me to simply squirm my way into, or out of it. Now, that may sound less than ideal, but really, it’s not that bad. Here is my process:

First, I sit on my sleeping pad with the bag pushed towards the foot end and slide my legs into the sleeping bag. Then I slide the sleeping bag up until my feet are positioned in the foot box. Next, I lie on my back, raise my hips and slide the sleeping bag over my bottom. Once this is done I sit back up and finish pulling the bag up and over my shoulders. Once this is done I lie back down and make any other necessary adjustments. Getting out is similar, but a little faster. Now this may sound alike a lot, but after doing it a few times, it is actually pretty easy and doesn’t take all that long. Also, I would rather use this method than unzipping it, lying inside, zipping it back up and then turning the bag so that the zipper was beneath me. Not that that method is wrong, it’s just not my preferred method.

And how could I wrap up a post such as this without including weights! As I mentioned, there are a number of variations that one can purchase this ZPacks sleeping bag in, so obviously weights will vary. As for my specific sleeping bag, which as I mentioned is a 20F bag, in a size long and wide (or standard) width, has no draft tube and includes the standard, stock 3/4 length zipper, it comes in at 19.5 oz (san’s roll top dry bag) on my personal scales. The listed weight is 19.8 oz, so that is pretty dang close, which is amazing that they have it nailed down so well. And to break the weights down even farther, according to the ZPacks website, the shell comes in at 6.7 oz and the down fill is 13.1 oz (these numbers have been confirmed that they are the same for both my previous version and the current version as of this writing). This is about a 66% insulation to total weight ratio, which is pretty impressive. Anyway, for a sleeping bag that for me seems to be pretty spot on for 20F and only weighs 19.5 oz, I am admittedly quite stoked about this!


The last thing I would like to mention is accessories. All of the ZPacks sleeping bags come with an appropriately sized cuben fiber roll top dry bag. Of course this bag is for “compressing” the bag to actually carry it inside a backpack, not for long-term, at home storage. Unfortunately, ZPacks does no supply a storage bag for their quilts so it is up to you to provide one, or simply store the sleeping bag either laid out, or hanging up. I myself opted to buy some material from War-Mart and then sew my own. It is large enough that it does not compress the sleeping bag at all, and being that it is cotton, it will allow the bag to breathe so it stays dry.

So, I think that pretty much wraps up my thoughts on this sleeping bag thus far after owning it for several months, and actually using it a handful of times in the field. I will admit that it took me a few years to actually pull the trigger on this sleeping bag, but now that I have it I am super excited that it is part of my arsenal!

Thanks again for stopping by! As I said, there are 2 other pieces of gear that I am planning to write up a PHGT on in the following days, so be sure to watch out for those too!


Disclaimer: I purchased this sleeping bag at full price from ZPacks in the spring of 2016. I am not affiliated with ZPacks in any way, and am not obligated to write anything about this piece of gear. So basically I am not getting paid to write this in any way and the above thoughts, comments, and opinions are my own. I just wanted to share my excitement about this quilt with my audience! 🙂

About Stick

My blog is essentially a record of my hiking career. Through it, I, and others, can see how I have evolved from a heavy weight backpacker, to a smarter, more efficient, lightweight backpacker. Through the use of video, still photos, and of course writing, one can see my progression, as well as check out some of the places I hike, and not to mention some cool, lightweight gear options. For me, my blog is a journal, but for others, I hope that it is an interactive learning tool to aid them in their own progression towards lightweight backpacking.
This entry was posted in Gear, Gear Reviews, Gear Talk, ZPacks and tagged , , , , , , , , , , . Bookmark the permalink.

16 Responses to GSMNP PHGT, Part 1: ZPacks 20F Sleeping Bag

  1. Dogwood says:

    Unless I missed it what length pad do you use underneath the ZP sleeping bag? Do you find a cold spot using a short length NeoAir or TorsoLite where the zip is exposed off the pad in temps below 30* – about 25* and to the 20* mark – – in your set up with no draft tube when the zip is positioned underneath?

    Most folks want accurate temp ratings to accurately compare sleeping bags and quilts. Bags already have this if they are EN rated as the best most UL conventional sleeping bags. With quilts there is no independent body doing this so were back to a similar pre EN ratings scenario with quilts. I understand EN ratings are not absolutes but at least they provide somewhat an even playing field for doing temp comparisons. This is very important for one as myself cowboy camping often taking a bag or quilt to and a little below the rating. I would expect a 20* bag to be a 20* bag without all the if’s, but’s, and and’s which seems to me a bit of grandstanding. The vast number of ZP bag reviews despite yahoo reviews don’t have reviewers doing this? which seems odd especially since UL philosophy has long mentioned taking a bag below it’s temp rating and beginning by an accurate temp rating. What’s the coldest you’ve had your ZP 20* bag and under what set ups and conditions? I find many ZP bag reviews lacking details about how often and under what scenarios did ZP bag users take their bags down to and perhaps 5* below their advertised temp ratings in the 10* and 20* bag models OR if they do this at all.


    • Stick says:


      If it is cold enough for me to use this bag, I am carrying my large NeoAir XLite, and even a 1/8″ ccf pad that I can layer either below (for protection) or on top (for additional felt warmth) of the XLite. Considering this is a full length pad, I can’t really comment on any coldness felt at the zipper, however, it wouldn’t surprise me if I did when the pad is not on something insulating me from the ground.

      As for conditions I have used it in, I described those in some detail in the “real world use” section above. This post was written in December of 2016, and since then I have used this sleeping bag 3 other times, once on a hike and 2 other times while at the 2017 ATKO. I can’t recall those conditions exactly off the top of my head, it wasn’t all that cold though, mid 30’s or so. I had no troubles with the bag though (and I shouldn’t have).

      My feeling with this quilt (so far) is that for me it is a 20-ish degree quilt. To me personally, this means inside my tent, and with a thin skin layer on, and of course a hood. As well as somewhat hydrated, and with a good meal in my belly. Honestly, if I were planning for temps consistently a little ways below 20F, I would likely go with my Helium Sleeping bag (although, it would be nice to grab a 10F bag… which I had a hard time debating between the 20F and the 10F…)

      As for the EN ratings, if I am not mistaken, I thought I saw somewhere (likely on BPL?) that a very few quilts were now being rated using the EN rating…? I think I remember a thread that Tim Marshall was discussing this in… I could be wrong though. Either way, as you mention, EN ratings are not absolutes, and while I too believe that they offer a fair “standard”, I still don’t believe that this exactly translates to how it works for each of us. There are so many variables involved, it’s hard to really, truly nail down a certain temperature rating. I know that I have felt a difference in how temperatures have affected me over different nights in the same bag. Saying all of that, I have always assumed (regardless of EN rating) that the “rated temperature” was assigned with all other variables covered, such as using an appropriate under pad, inside a tent or shelter, fed and hydrated, and probably even with a thin skin layer on too. These also happen to be the stipulations for EN ratings too.

      I will say that I plan to use my Zpacks sleeping bag next year on a 20 day JMT hike, and given my (even limited) experiences so far with it, I feel that it will be just fine for me. I do plan to cowboy camp several nights on top of (or near) high passes (because I really want to do that!) but it will also be a touch and go thing. I expect some nights to likely be at least at the 20F mark, and maybe even a little under, however, I figure most will be a little higher. In this light, I do say that this is a 20F bag for me, considering I understand how to use it, and what to expect. I can’t say that for everyone though…

      I know I went all over the place, and still didn’t really answer your question as you had hoped, but it’s the best I can say… I hope that does help some though.



    • Dogwood says:

      THX Stick. You did clear up some questions. My post rambled so you mainly followed.

      I feel frustrated with some quilt assumptions and conclusions even as a reg quilt user.


    • Dogwood says:

      I find myself debating the same thing you did 10* or 20*. That factors in the temp rating accuracy of the bag itself while attempting to balance UL gram weenie ideals, sleep systems with the bag the main component in the system, greater potential sleep system complexity, and personal usage. Again, thanks for the prompt reply.


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  5. BigBadJohn says:

    Excellent review. I have this exact bag… sane size, color, everything! I will say I regret not getting the draft tube. I move around a lot and it isn’t easy to keep the zipper below me. I’ll probably get them to add one to it.


    • Stick says:


      I was unsure about that when I ordered mine, but not that I have used it a few times I am happy without it. I more around a good bit at night but I tend to turn inside my bag so I don’t have a problem keeping it beneath me.

      Also, I am not sure if they will add it to the bag. I know they stopped doing custom work some time ago… maybe something like that they could… I dunno. I knew one day they would be too big to keep doing this stuff though… Let us know what they say!



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  7. Bungzy says:

    Great review. I’m a big Zpacks fan, and I’ve given their sleeping bag (same one as you) a try. It’s a well-made product, but I have to say that the Katabatic quilts, when paired with the right mattress is significantly warmer (and more comfortable), while being comparable in weight.


    • Stick says:


      I have never even laid hands on a Katabatic quilt, but I feel it’s safe to say that there is no doubt Katabatic makes some fine quilts… and it’s not uncommon to see them described as the “Gold Standard” for quilts, same as Western Mountaineering is for sleeping bags. As well, folks seem to report that they are optimistic with their ratings, as you are saying. What I think sets the ZPacks quilts apart from Katabatics though is that they offer a zipper, and they are just a bit more simple in design. These things actually result in a lighter weight and a little less cost than the Katabatic quilts.

      Saying that, if I could own them all, I would love to own one, same as with a WM bag… I think it’s great that all these companies exist, making similar items but with their own feature set. What is for sure similar though is that they are all well constructed, effective and use high quality materials. I don’t think you will go wrong with any of them… it just depends on what you are after.

      Thanks for stopping by and commenting!



  8. Vince Varriale says:

    How do you feel about this “bag” getting down into 0 degree weather? I know it is rather at 20 but is there enough room to sleep with layered clothes on? I’m trying to decide to pull the trigger on this or a good 0 bag since I do a lot of winter hiking in the SE.
    BTW, glad to see you out and about!


    • Stick says:


      For mine in particular, I think I would survive at 0 with all my down layers, but not happily. If you wanted to take the ZPacks bag down to 0 I would recommend to go with the 10F bag rather than the 20F bag (what I have) and make sure you get it wide enough so that you can layer your down layers inside without compressing them. For me, I wanted this particular bag to take me to around 20F and just under if needed. I believe it will work for me to do that.

      Hope this helps, and yes, it’s been great getting back out! Thanks!



  9. mikeetheviking says:

    Thanks for the detailed review!
    I appreciate your “all things considered”
    approach to gear talk!


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