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Extreme winter sleeping bag system advice?
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Paul Lundblad
(paullundblad) - F
Extreme winter sleeping bag system advice? on 02/19/2012 08:34:03 MST Print View

I'm going to be moving to Northern Sweden this year and am working on getting geared up in the US being that most everything will be cheaper here. I expect to be doing some winter camping in bivouacs, snow caves (maybe), and/or tents and the temperatures could get down to between 0ºF and -20ºF while I'm out there. It's been recommended to me to get a bag with at least a 0ºF rating, with preference being an extreme temperature of at least -20ºF if not -30ºF preferably in synthetic being that wet down could be life-threatening out there.

The bags on the table;
1. Mountain Hardwear Lamina -30 - cheapest, synthetic fill, coldest advertised rating.
2. Mountain Hardwear Phnatom 0 (Women's because of my build and extra insulation in torso and feet) - Could I comfortably/reasonable get below 0ºF with a VBL and bivy sack with this set up?
3. Big Agnes Hahns Peak SL -20 - 3.5 lbs, cheaper than the Wraith, 800 fill down, yet no insulation on the bottom (comes from pad only) and only DWR on the outer shell.

I know everyone recommends Western Mountaineering or Feathered Friend etc etc, but of these bags, which would be the best bet, and what precautions should be taken to keep it dry while in use? Would it be sufficient to go with a bag with a rating of 0ºF or somewhere in the middle and rely on a bivy and VBL for extra warmth down to -20? Lots to consider in such an investment, so sorry for the slew of questions, but I appreciate advice from the experienced.


Locale: Western Michigan
Extreme winter sleeping bag system advice on 02/19/2012 08:59:16 MST Print View

When the family adventured across Michigan’s Shore to Horse Riding and Hiking trail on xc skis pulling a pulk back in the 70’s I used a North Face 20*F Bag, sleeping bag VBL and 1.5cm closed cell blue foam ground pads. Many mornings it was in the single figures and one night in particular we experience sap in the conifers “snapping”. Never had any issue of being cold or extreme wetness. You will have frost in your tent and on the top of your bag but shaking it off solves the problem.

Addison Page
(Nihilist_Voyager) - F

Locale: Down the Rabbit Hole!
Possibility on 02/19/2012 09:07:44 MST Print View

I saw a -40 degree bag the other day on REI mobile, Marmot CWM EQ -40, while I was tossing back and forth the idea of making my own deep winter bag...

Looks not too shabby for it's warmth I guess. 5 pounds for a long, almost three pounds of it insulation (48oz), shell described as a waterproof breathable laminate, though there's no listed EN testing for it

719.00 for a long, 699 for regular

Check it out, if it doesn't do what you want, return it!


Edited by Nihilist_Voyager on 02/19/2012 09:09:44 MST.

Dustin Short
(upalachango) - MLife
Re: Extreme winter sleeping bag system advice? on 02/19/2012 09:09:00 MST Print View

You're forgetting another key aspect of pushing your sleeping gear into colder temps, your clothing. If you're camping in 0F weather you are bound to have some puffy insulated jackets and pants which you can wear to bed or drape over your bag. So you'll want to make sure you get a bag cut loose enough that it doesn't compress these layers.

Most people are going to suggest down since pound for pound nothing compares. As such they will advise against any shell that prevents moisture from escaping because that will lead to buildup inside the bag increasing weight and decreasing warmth. VBLs go a long way to prevent that. At 0F and colder there's little chance of getting your bag wet from precipitation, the air is just too dry, but it will get wet from perspiration.

If in a snow cave conditions are much warmer (usually around the freezing point) but wetter which is where adding a bivy with a good DWR is useful (something with Momentum or Intrepid tops and a waterproof bottom like silynylon).

To give better advice about the WM, FF, or Valandre bags we'd need your measurements. Circumference of your feet, hips, shoulders are how those bags are sized (plus height).

As an example look at Western Mountaineering's 6ft Lynx and Kodiak. The Kodiak has 30oz of down and the Lynx has 32 oz, not much of a difference with so much down. Yet the Lynx is rated a full 10F warmer (-10F vs 0F for Kodiak) because it is much narrower. This is great if you're only sleeping in base layers, but the Kodiak may be easier to layer your insulating clothes and push into colder temps than the Lynx...

[Added] Also on last thing, don't skimp on the sleeping pad. You'll probably lose more warmth to frozen ground than the air and a good (ie Down Air Mattress like exped or kookabay, or stephenson's if they fix quality assurance) will be worth it's weight in gold.

Just a primer of things to consider, I'm sure the Canadiens and Alaskans will have a lot more to say when they chime in.

Edited by upalachango on 02/19/2012 09:11:09 MST.


Locale: Western Michigan
Old timers input... on 02/19/2012 10:17:24 MST Print View

While all the equipment recommendations are great, DON’T forget equipment only insulates you from the cold. The other variable you need to look into in extreme climates and temperature conditions is the ENERGY SUPPLY you provide your body in the form of food/cal intake.

Edited by KENLARSON on 02/19/2012 10:18:14 MST.

Robert Cowman
(rcowman) - F

Locale: Canadian Rockies
Re: Old timers input... on 02/19/2012 12:53:27 MST Print View

I live in -30 temps in the winter similar to what your moving too. (I Live in Northern Alberta) The wt down myth is myth. its so easy to keep down dry in the winter. synthetic bags are in my experience garbage. they don't stay warm take up your whole pack and don't last. (My experience is based off a MHW Lamina 0F, MEC -15C and a Sierra Designs 0F cant remember the name) Get a down bag. Yes you can use your clothing as extra warmth but don't go get a 20F bag and try to get all your clothes in it. They're way to small for a down parka(like a full on 32-40oz belay parka not a mont-bell)

I Do suggest insulated pants Like Eddie Bauer Igniter pants(as an example) and insulated socks like down socks. easy to pull over stuff and adds warmth in camp. I suggest a 800fill down bag at least 0F for winter depending on your conditions. Look more for a -10F for deep winter. also note that a snow cave can get really warm inside and get to almost 30F inside with multiple people in it or a stove/lantern.

I Personally avoid waterproof sleeping bags because the condensation build up inside is way to much and collapses your down in a hurry.

Edited by rcowman on 02/19/2012 12:54:44 MST.

Paul McLaughlin
(paul) - MLife
Re: Extreme winter sleeping bag system advice? on 02/19/2012 15:48:28 MST Print View

How long do you expect your trips to be? Makes a big difference in terms of how critical moisture management in your sleeping system is going to be. 2-3 nights is very different from 5-7 nights or more.

Paul Lundblad
(paullundblad) - F
The final theory for the final decision... on 02/20/2012 07:49:54 MST Print View

Thanks for all the tips. It's great to know that it is feasible to keep down dry while camping out in the winter without a lot of difficulty, and with the addition of a VBL and a bivy in that kind of temperature it looks like there's a way to make this work.

It appears that the decision has been narrowed down to the MHW Phantom 0 or the Big Agnes Hahns Peak SL -20, and I'll probably go about getting a cheap VBL (like a heat sheets bivy, which I read about on BPL), and worry about an outer bivy later. It appears that I don't have to worry too too much about how breathable the bivy is if I'm using a VBL, is that right?

So here's my theory that I'd appreciate your word on its validity:

I hear that the MHW Phantom 0 is a true 0ºF bag, and that all BA bags are optimistic in their ratings. The MHW is more of a narrow cut (60" shoulder girth), so putting the down parka over it and a VBL inside of it could theoretically bring its rating down below 0ºF (-10 maybe?). I'd fit into a regular length women's version of the bag, which puts more insulation around the feet and torso, and being that I'm a man that might functionally put the base rating of the women's bag a little below 0ºF. Maybe?

The BA Hahns Peak SL -20 bag has a 67" shoulder girth with the same length as the MHW women's reg bag, so I'd have more space to wear my parka inside of it (over the VBL) and more space for gear/changing in the morning. Theoretically if this thing's actual comfort rating is more like 0ºF or a little below, a VBL and a down parka inside should bring it down to its advertised rating, and maybe all that combined would make it a warmer bag than the MHW Phantom 0 with a VBL and parka over it.

Does this logic jive? Which would the gurus take as a wiser option between the two? Barring food intake and sleeping pad set up, would this seem like a wise way to go for camping between 0ºF and -20ºF? I know everyone suggests going for WM or FF etc etc, but I'm really only looking at these two right now. Thanks so much!

James Ratzloff
(jeratzlo) - MLife
Fleece Liner on 03/26/2014 10:01:03 MDT Print View

I slept outside on my deck this winter until Christmas to test my winter sleeping gear (in Colorado). I used a Mountain Hardwear Wraith Down Sleeping Bag, rated to minus 20. I found that on the coldest nights which were below zero, I would wake up chilly sometime in the night. What solved that is using an inexpensive fleece liner inside the bag.

I have three border collies who backpack with me. One would stay with me on the deck, no matter how cold it got.(Hayley - grey/white blue merle) The other two would go in through the dog door into the heated laundry room. All three are good dogs - but Hayley is very very loyal.

Bob Gross
(--B.G.--) - F

Locale: Silicon Valley
Re: Extreme winter sleeping bag system advice? on 03/26/2014 12:02:19 MDT Print View

Back in the 1970s, I was inexperienced in the mountains. Even though I purchased a good down sleeping bag, I didn't understand really how to get the most out of it. As a result, for one trip the bag got totally soaked in icewater which led to a nasty case of hypothermia.

After that, I set out to learn the ropes about down sleeping bags. All of the other advice here is sound, but there is a little more that helped me. It is kind of a psychological game. I think of snow around my sleeping bag as being a poison, and it will be trying to leak in and contaminate the bag with moisture. Sure, on a nice day you can hang your bag over a warm rock and let it sun-dry. But you can't count on nice days with sun. So, initially at least, go overboard in protecting the bag from snow that might melt into water.

A good CCF sleeping pad is one help, about twice the thickness of whatever you use for summer. A good bivy sack might possibly help, especially if you are in a snow cave.

OTOH, snow can be a good insulator from the cold if you manage it correctly. The inside of a snow cave can be quite damp, and your sleeping bag will absorb water from anyplace it touches. So, the thinnest layer of plastic sheet, mylar space blanket, or anything similar can make a barrier between the snow cave and the sleeping bag.


Valerie E
(Wildtowner) - M

Locale: Grand Canyon State
Re: Extreme winter sleeping bag system advice? on 03/26/2014 12:40:34 MDT Print View

I own the Women's (long) Phantom 0, but I also own a -30 down bag (I lived in Quebec most of my life, and did winter camping).

You never said whether you are -- generally -- a cold or a warm sleeper. That info would REALLY help for this.

I am not so sure that the Phantom is that true to its temperature rating. I think, for me (being a cold sleeper), it's more of a 10-15F bag.

+1 on thinking about food/drink for winter camping. I found that a nice hot cup of tea before bed made me warm up really quickly. Another small detail you'll want to remember is that if you're in a snow shelter (like a Quinzhee), the temp will not get much below 32F because of the insulation of the snow -- so you'll need less bag for those trips.

My -30 Wild Cat bag may interest you. It's made by a small Canadian cottage manufacturer called Taiga Works, and it's a really good deal for the money. My old backpacking buddy has asked me to leave it to him in my will, LOL! Here's a link to the bag, which may give you yet another alternative (I have the 800 fill):

I have no connection with the company (other than that I own that bag), but I can vouch for it being VERY warm, comfy, and well made.

Andy F
(AndyF) - F

Locale: Ohio
Re: The final theory for the final decision... on 03/26/2014 12:51:50 MDT Print View

A bag-style VBL is going to make it tricky to use insulated clothing very effectively. You can't wear insulated clothing inside the VBL because it will become wet, degrading the insulation value. You could pull the VBL bag up to your armpits and still wear a down jacket. That would leave only the hood and shoulders of the bag needing to be dried to prevent loss of loft due to moisture.

It's probably best to get an eVENT bivy to cover all situations, as you might need a breathable bivy in a warmer snow cave, or a winter "heat wave."

Dena Kelley

Locale: Eagle River, Alaska
"Extreme winter sleeping bag system advice?" on 03/26/2014 16:46:01 MDT Print View

I took a class on winter survival that included multiple weekend outings. We did snow shelters, tarp shelters, debris shelters...anything but a tent.

In my experience- snow shelters are awesome. They are quiet, wind-free, and WARM by winter standards. The interior of a snow cave will be right at freezing 32F/0C no matter how cold it is outside. I always lined my snow caves with a space blanket, then my CCF pads (I used two, stacked) then my sleeping bag in a bivy (protection from ceiling drips). Be diligent about perfectly rounding your ceiling, because any bump becomes a drip point. Dig out a shelf for a candle- it will quickly create it's own chimney through the snow, and one candle provides excellent light inside the snowcave and warms it a bit as well.

Tarp shelters- and tents, for that matter- are colder and noisier. But sometimes necessary, if there is inadequate snow depth or the snow has the wrong consistency for a snow shelter. At the time I used a similar system- space blanket on floor, then CCF pads, then bag inside bivy. I often had hot water bottles which I heated right before bed that I used to bolster my sleep system. I always slept in a heavy 300 weight fleece balaclava that had full neck coverage. Bury any water bottles you aren't putting in your bag upside down in the snow, so any ice layer forms on the bottom of the bottle, not the top. Pull your boot liners out and put them in your sleeping bag to help them dry and stay warm.

Rick M
(rmjapan) - F

Locale: London, UK
Re: Extreme winter sleeping bag system advice? on 03/26/2014 17:06:15 MDT Print View


Edited by rmjapan on 06/21/2015 11:41:23 MDT.

Matt Dirksen
(NamelessWay) - MLife

Locale: Mid Atlantic
Re: Extreme winter sleeping bag system advice? on 03/27/2014 11:01:11 MDT Print View


What sleeping bag (and groundpad) do you currently have?

Is it possible to get a bag to double up with what you already have? There are many posts on BPL about double bagging in the winter, and how advantageous it is. I recommend looking into them. That way you also have more options when a zero bag is both too warm and too heavy on a given weekend.

Also, one thing is the temperature rating, another is the permeability of the bag. Sleeping in a tent vs. a snow cave vs. the open air are all very different, and might warrant different approaches, depending on the temp and RH.

Fwiw, VBL usage is something you should definitely try out and get used to, before your committed to it it on an extended trip. There are just as many people out there who swear by the technique as there are who swear at it. For many of us, I suspect, the idea of actually trying to fall asleep in one's own sweat is probably the last thing we'd ever wish upon ourselves. The lack of good sleep with too much tossing and turning during the night, could impact the vbl's effectiveness.

(RobertM2S) - M

Locale: Lake Tahoe
Cave building is hell on 03/27/2014 15:01:31 MDT Print View

If you are going from place-to-place-to-place, that is, not setting up a basecamp where you will sleep for several nights, in my opinion, a tent is the only practical option, unless you are just dawdling along and not using up much energy. I have spent hours building really big caves, where several people with different shovel sizes come in handy. I don't think most people could do that day-after-day, it’s just too strenuous.

Bob Gross
(--B.G.--) - F

Locale: Silicon Valley
Re: Cave building on 03/27/2014 15:21:13 MDT Print View

Yes, building a real snow cave can be very time-consuming. Tenting is quicker, but it isn't as warm for sleeping, and it is obviously more weight to carry.

There is a compromise that we established 15-20 years ago. We call it the Sierra Nevada snow shelter. It seems to be quick enough, yet low-weight. This requires one large flat tarp, typically of a size 8x10 or 10x12 feet.

Let's say that you have a team of four cross country skiers. You've skied all day, and it is time to camp in six feet of snow. Step 1. With skis on, tamp down the selected shelter area. Step 2. Stretch the flat tarp out on the surface and mark the outline of the tarp edge on the surface. Remove the tarp. Step 3. Using shovels, you start excavating snow blocks from the inside of the marked outline. You want to excavate blocks two layers deep. You are creating a hole within the rectangular outline. If you have two or three skiers with good shovels, then this can go quickly. They hand the blocks to the stacker. The stacker stacks the blocks around the outside of the marked outline, slightly overlapping the blocks. You should be able to go three blocks high, and the hole is two blocks deep. That makes a total space five blocks high, and that will be about four feet high. Step 4. The skiers extend and connect their poles together to build a framework of sorts that fits over the top of the snow block wall. Then the flat tarp is stretched over it and fastened down on the wall. Step 5. One corner of the wall is knocked out to make an entrance. The best corner is not the windward corner. It is necessary to step down into the entrance.

Typically, we have space for about four sleeping bags inside. We set up a single stove in the entrance and do all cooking there. If it shows during the night, that will accumulate on the tarp. If it starts to load up too much, just kick it and most of it will slide off.

Step 6. In the morning, you clear out of the shelter, remove the tarp, and remove the poles. Leave the walls of the shelter as a monument.


rOg w
(rOg_w) - F

Locale: rogwilmers.wordpress
deleted on 03/27/2014 17:58:18 MDT Print View


Edited by rOg_w on 04/02/2014 05:49:55 MDT.

Bob Gross
(--B.G.--) - F

Locale: Silicon Valley
Re: Extreme winter sleeping bag system advice on 03/27/2014 19:02:27 MDT Print View

I agree with everything that rog said, except I think that the people from Michigan stole it from Californians.

We've done a variation of that, and instead of a flat tarp, we used a shaped tarp. Then we supported it near the center with two extended ski poles. The variation that you use kind of depends on whether you expect snowfall overnight.

Also, it helps if you halfway close the entrance by placing a backpack there. That helps keep excess snow out, but you don't want to close it up too much. People have to breathe.


rOg w
(rOg_w) - F

Locale: rogwilmers.wordpress
deleted on 03/27/2014 19:26:45 MDT Print View


Edited by rOg_w on 04/02/2014 05:50:30 MDT.