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Alpkit team bivvy 16 below zero

By Kenny Stocker | 28, Jan, 2009

Team Alpkit give up a comfortable night in a gite to experience a winter bivvy in the mountains.

We spent Saturday night in the Fournel valley under the stars. The sky was clear, the snow was crisp underfoot, the temperature was 16 below zero. We kept warm during the evening insulated by our Filo jackets, supping hot soup and huddling around the bonfires. We kept this going until 2am when the fatigue from the past two days finally caught up with us. Neither Ashleigh nor Jenni had camped out in these conditions which made their decision to join us in the bivvy all the more awesome! imageJim was so impressed by the igloo some of the other bivouacers had constructed that he couldn't resist getting in on the action. Finding a sturdy shovel he set to work excavating a large hole and kept going until it was large enough to sleep seven. It never did get a roof but it would provide us with some shelter if the wind picked up during the night. Each of us was sleeping with an Airic inflatable mat on top of a closed cell foam mat. We then had a combination of Alpkit sleeping bags inside Hunka bivvy bags. Ashleigh had her old style AD700 beefed up with a PD400. Jenni had a prototype AD1000, this was rated by Leeds to -30, but as she said she sleeps really cold. image The first problem was to get in the bags while keeping the snow out. With a single bag it is not so much of a problem, however with two bags things are not so easy. It is kind of like getting into a kayak, you have to balance behind the opening and slide your feet down into the bag. A sleeping bag that has been laying around in the snow is not going to be warm when you first get in it. When this is -16 you don't really want to strip down to your pants and just slide in. So most people keep some layers on and remove them as you warm the sleeping bag up. For us this meant baselayer, tshirt, fleece (maybe two), down jacket, gloves at wooly hat. Shoes are placed inside a rucksack to prevent snow blowing into them over night, if they are wet you may want to put them inside your bivvy to stop them freezing. image Once inside the bag you have the problem of where to put your garments when you take them off. Ideally you want them to be warm when you put them on again in the morning, but space is limited especially when you are fighting against two sleeping bags which want to rotate in opposite directions. Eventually we got ourselves sorted and all we had to do was throw our heads back and gaze at the stars. The night passed quickly, well I guess it would do if you don't go to bed until 3am and you have Francois Lombard waking you at 6.30. Both Jenni (JW) and Ashleigh (AN) were persuaded to emerge from their cocoons and confront the new day or face a long cold walk back to the village. It was not a surprise that both of them claimed to be cold.. but let's examine that more closely.. at least they were still alive. One full breakfast later and with the sun shining on our faces we asked the girls some leading questions..

AK: How did you feel when we told you that we would all be bivvying on an ice climbing trip?
JW: A bit worried that I really was going to be hypothermic by morning. I was worried that I wouldn't get a chance to warm up before getting into the bag, especially if we had been doing activities during the day. I simply didn't believe that I would be warm regardless of which sleeping bag I took.
AN: My first thoughts were that you'd have to be crazy to bivvy outside, in the snow, in the Alps at winter- it'll be ridiculously cold. Why would you do that to yourself? However, after these initial thoughts I started to think about what an interesting experience it would be and despite my concerns of freezing I was actually rather psyched to try it out.
AK: What was your previous experience of sub zero temperatures?
JW: Camping on the Inka Trail in Peru in June. I was using a synthetic bag that was supposedly a 4 season bag but I doubt that very much as it had been washed repeatedly between treks. We were at altitude and the minimum temperature was -3 at night in clear skies plus we'd been walking all day so had been burning lots of energy. I always feel cold after exercising.
AN: I don't think I have really experienced any extreme sub zero temperatures before, other than general cold British weather.
AK: It was a smashing evening at the bivvy, the sky was clear, there was no wind and the moon was ripe. At this point did you still have concerns about what was to come?
JW: Yes! Although the fact that it was so still made me feel better. I think I would have cried if it had been snowing or windy or both.
AN: The atmosphere at the bivvy was absolutely amazing. The surroundings were so beautiful with the full moon shining on the mountains so they were visable even in the middle of the night. However, I was cold just being there (unless I was stood right next to one of the campfires) so I still had my concerns about freezing in the night.
AK: The sleeping bag was just one element in your total sleep system. How aware were you of the other factors that would determine your comfort during the night; such as preparation, sleeping mat, bivvy cover, physical condition, wind chill, transition from and to sleeping bag?
JW: I feel the cold very quickly and this process is accelerated if I have exercised during the day and allowed sweat to cool on my back. Therefore I had made a concerted effort to ensure I was warm before getting into the sleeping bag. I messed around with the number and type of layers I had on and by the time we headed to bed I was confident that I was warm as possible. I also went for a quick jog around the bivvy site too to get all my muscles and limbs moving before tucking myself up for the night. As I mentioned in the question before, I was really pleased it wasn't snowing or windy as that would have really depressed me plus I hate getting into a damp sleeping bag in damp clothes. I had a Hunka XL which meant I could tuck all my stuff inside which I think was vital and I used a Fat Airic with a closed cell foam mat. Having now slept on snow, I would always, always recommend a closed cell mat as you can't beat them for basic insulation. My Fat Airic was rather soft as it was too big (and too frozen!) to properly inflate and therefore my foam mat provided me with the all-important insulation from the snow. Getting in an out of the sleeping bag was fine as my XL Hunka allowed me to dress and undress inside my sleeping system.
AN: I knew that getting up in the morning was not going to be particularly pleasant and I knew that a sleeping mat would be particularly beneficial. Other than that I didn't really know what to expect or what else could prevent me being too cold. In fact, physical condition I only just realised was a factor when reading this question.
AK: Once the sleeping bags were laid out and you slid inside your bag did you think that you would survive the night in comfort?
JW: I started to feel hopeful! I was pleasantly warm and once I had found all the toggles etc and was able to pull everything really tight, I was actually quite cosy.
AN: I really didn't like getting my bivvy bag and mat all sorted out for sleeping because it was all frosted over and I felt cold. But once I was all sorted in my sleeping bags (after much wriggling around getting everything lined up right) I did actually feel ok- I was suprisingly warm.
AK: What did you wear inside your sleeping bag? Did you need to add / remove clothing during the night? if so what were you trying to achieve and how did you manage that process?
JW: A pair of walking socks, silk/cotton leggings, a long-sleeved merino thermal top, a long-sleeved fleece top. I woke up about 2 hours from dawn and had cold knees and feet. I had an XL sleeping bag which was too long for me so I tucked my Filet around my feet at the bottom of the bag and placed my Filo over my knees and went back to sleep.
AN: If I remember rightly, I wore thermal trousers, a tracksuit and some softshell trousers on my legs and 2 thermal base layers, 2 light fleeces, 1 heavy fleece, a softshell jacket and my down jacket on my top and didn't add or remove anything during the night. Retrospectively this may have been a mistake as I think it made it harder to get out my sleeping bag in the morning and there was the possibility that my down bag could have been slightly compressed by all the layers.
AK: How well would you say you slept?
JW: Pretty well. We went to bed at 3.30 am and I woke only when Jim started to rouse us. I usually need 8 - 9 hours' sleep so I'm not sure how well I would have slept had I gone to bed at a normal time.
AN: I slept really well. I only felt uncomfartable when I woke up in the morning and my nose was cold.
AK: What best describes your temperature during the night? freezing, cold, chilly, comfortable, warm, hot, sweating.
JW: Just warm enough. Not cold enough to do anything about it but not toasty. Had I slept for longer, I think I would have needed another layer on my legs and possibly my top half.
AN: I was pretty comfortable. A little chilly in the morning.
AK: Did you have problems regulating your temperature during the night?
JW: Nope, I was warmer as I went to sleep but that's because I spent so much time wiggling around trying to find my toggles! I then cooled to the temperature that I would remain at until morning.
AN: I just slept and made no effort to regulate temperature.
AK: Did you have any cold spots, if so how did you manage to warm them up?
JW: As before, I tucked my Filet around my feet at the bottom of the bag and placed my Filo over my knees.
AN: The only cold spot I had was my face in the morning. I didn´t manage to warm that up but got up within half an hour of feeling cold so it wasn´t too much of a problem.
AK: What was your first thought when you woke up?
JW: I'm alive! The moon has gone.
AN: My nose is cold and wet (think it must have been condensation) but the mountains are beautiful!
AK: How keen were you to get up in the morning?
JW: Keen - I wanted some coffee and a croissant - I was starving!
AN: I wasn´t too thrilled about the idea of getting up. Despite having a cold nose- I knew I was going to be very cold once getting out of my sleeping bag.
AK: Having survived and had time to reflect on your experience how would you describe your comfort level during the night?
JW: Good considering the conditions and my lack of experience of sleeping on snow.
AN: It was actually pretty comfortable. The worst bits were getting in and out the sleeping bag. Once inside the sleeping bag I wasn´t at all cold.
AK: Some people may think that because a sleeping bag is rated to -30 they are guaranteed a good night's sleep. Is this a fair assumption from your experience?
JW: No (but I do sleep exceptionally cold). It also depends so much on so many factors. Experience is the key as it is with anything.
AN: I think that would depend on the temperature outside!
AK: Sleeping bags come with comfort ratings but do you think that 'comfort' at -16 can ever be comparable to 'comfort' at +18.
JW: For me, no. You have to put so much more thought and effort into achieving comfort at -16 whereas at +18 you just get into your sleeping bag and go to sleep.
AN: No, I don´t think comfort is the same at -16 as it is it at +18. However, I was surprisingly comfortable in my sleeping bag and bivvy cover and to wake up surrounded by the snow and mountains is an amazing experience- totally makes up for not being quite as comfortable as you would be at home in bed. Plus, it wasn´t that bigger difference in comfort!
AK: How has this experience altered your understanding of your kit and it's limitations?
JW: It hasn't really changed my understanding to be honest. I would say I was aware of how the kit would perform, it was me that I was worried about! Although, I did learn to trust the comfort rating a little more.
AN: I was really surprised how well the kit managed to keep me warm. I really thought I was going to freeze no matter what anybody said. I know it can´t keep me fully warm as if I was at home- but it was very close. I am rather impressed by that. It was -16! And I wasn´t cold!
AK: How has this experience altered your understanding of your own limits in a mountain environment?
JW: It's proved I can do it if I have to but that it is something that I'm perhaps not best suited for if it was going to be for more than one night or if there wasn't a 'safety back up'. I was only just comfortable and I'm very aware it wouldn't have taken much for me to cross the very thin line between being fine and being at risk of hypothermia. Had it snowed, had it been windy, had I not had a three course, hot and filling meal, had I not had plenty of water and lots of clothes, I would have been very, very cold and very, very miserable!
AN: I coped better than I thought I would in the mountain environment. I don´t like being cold and I was not sure how well I would cope with it. With aid of the gear, I feel confident enough that I could bivvy out again quite happily - not regularly, but I would definitely do it again!
AK: Any other useful nuggets?..
JW: I was really, really pleased to get the opportunity to try the kit and to push myself in a 'safe' environment. Knowing I had the knowledge and support of the rest of the Alpkit team made it much easier to do and their combined experience helped me make informed choices about what I needed in order to prepare for the bivvy.

So what conclusions can we draw from our night of sleeping on snow..

Much to our relief our two volunteers were both very much alive in the morning. They claimed to be cold but we were in the middle of the mountains and at least 45 minutes from a hot mug of tea. After a few minutes of packing away their bivvy gear they had warmed up considerably. Let's not forget that neither had previously bivvied or slept at these temperatures and so approached the night with a certain amount of trepidation. Jenni had a bag rated at -30 lower limit of comfort and Ashleigh had an old AD700 (-15) and PD400 (-3), both were wrapped in a Hunka bivvy. Considering our location it is no surprise they felt cold when they awoke however Col who has had more experience of bivying was in a SkyeHigh 800 (-10) with no bivvy cover. On paper he should have been colder but he slept comfortably only dressed in his baselayers. When you are sleeping at these temperatures do not expect to be as comfortable as you would be in the summer even if your sleeping bag rating implies that you should be. In the winter each process takes more time and effort, every movement demands care and attention as you try and conserve every single degree of hard earned warmth. With so many variables at play it is difficult to tie down the concept of comfort when bivvying. We had 9 people in our group and the chances are that each of us will have different memories of the night. Comfort ratings can only be appreciated by getting out, experiencing the environment and using the gear in context. If you have never camped in winter before don't just go to a shop, demand a -20 bag and expect that you will sleep comfortably at -20 on your first night just because the gnarly shop dude can. Build up to it, get some experience first, understand your physiology, understand your environment. There is some debate as to whether it is better to sleep naked or in baselayers. Our answer is very much a practical one. The bag is cold when you get into it, you may have to get up in the middle of the night to take a pee, it might be snowing in the morning.. you have guessed it we wear baselayers in winter and leave the theoretical question in the lab. image

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