Snow Cave question

[DanO]

Hello,

 

I am not really a newbee, but never had to actually

use a snowcave. Can one use a down sleeping bag without a cover

sack? Will the bag get soaking wet and how long it will take?

 

Thanks

Dan

Edited January 3, 2007 by DanO

[Clavote]

oh, it will get wet alright. You need a sack or a bag with a waterproof goretex material. Lots of dripping in a snow cave.

It does not take long for it to get wet either.

 

I've seen people bring down while using a plastic sheet on the snow floor with a floorless pyramid type tent and they fared OK. But those were short two day trips. On a prolonged stay in a cave I would want a sack. I also used a synthetic bag on hood for a long time and I have to say the synthetics dry real quick if they get wet, but you do get a bulkier and heavier bag than down.

 

I am looking at down/synthetic hybrid bags, but most of those are summer rated bags.

[Couloir]

To help minimize--though not completely eliminate--the moisture, make sure you have good ventilation without sacrificing heat retention. Also, make sure you smooth out the ceiling and walls as much as possible. Any little "peaks" will be where water potentially drips. Also try and not press directly against the walls while you're sleeping, or waiting out the weather.

 

A bivy sac is great, and some sort of a barrier between that and the snow will also help keep you even dryer (and warmer). I also echo Clavote, synthetic bags will be much more useful in a snowcave than down.

[genepires]

Some down bags have a waterproof breathable outer shell already. This would be fine for inside a snowcave. There is some dripping but not so much that a bivy sack would be needed if your sack already has a good outer finish. (like water getting through the seams which are usually not taped on a sleeping bag)

 

If your bag does not have any kind of good outside material (driloft, event, epic, ect), then any amount of dripping will saturate the bag and you will need some kind of bivy sack. Your bag will get a little damp anyway due to sweat.

 

Just my opinion, but synthetic bags are crap. Never warm enough, always weigh too much and never compress enough for my too small pack. stay natural, exercise common sense with your gear and stay with down.

Edited January 3, 2007 by genepires

[DanO]

Hello,

 

I have a down bag, I have tried the synthetic bags

and found I didn't like them near as much as down for packablity

and warmth. I am thinking more of using a snow cave in a emergency situation. Something like a summit attempt while carrying a shovel, stove and sleeping bag. Maybe better off carrying knothing and committing to getting down no matter what, this is what I normally do. Thinking about raineer or denali the slightly taller peaks where chances of getting caught out are slightly greater. I hate the weight and wondered if I could get

away with only a sleeping bag, hence the question. By the way

I use a stephenson's warmlite sleeping bag which has a built in

down filled air mattress, it helps keep the bag dry bottom up

as well more comfortable, like bed at home, spoiled rotten I am.

 

Dan

[OrganDonor]

Yes, you need something betweeen you and the ground/snow/ice. Without a pad or bivy sack of some sort your basically sleeping on ice.

[mattp]

I have used down bags in snow caves for years, and very often I use a bag that does not have a goretex or similar shell. I have never used any kind of sleeping bag cover. If you are careful to make the ceiling dome-shape and shave off any points that cause dripping, you won't get much drippage. If you stay on your pad, you won't be lying on the snow floor. With a bit of care, you'll probably stay drier than if you were in a tent getting frost on your bag.

[montypiton]

My experience echoes mattp's. I used down bags in snow caves for years before gore-tex was invented, never used a cover, and had comfortable trips. Doubling up on foam-pads underneath has worked well for me, and, as they said above, a smooth ceiling drips less than one with lots of "pointies". Another consideration - it's easy to inadvertantly overheat a cave. You stay lots drier if you can maintain the temperature below 0 centigrade. Larger caves are easier to move around in without rubbing against walls & ceilings, and they don't overheat quite as readily. If you're considering Denali, learn to build igloos; - the shelter of choice among the guides & climbing rangers there.

[mattp]

The biggest problem with getting wet in a snowcave lies in getting soaked when digging the thing, and then bringing all your wet clothing inside and maybe wearing it in your sleeping bag. Before you work up a sweat digging and lie in the snow hauling snow out the door, strip down, or maybe wear your shell gear but none of the moisture soaking layers beneath. Dig your cave on the steep side of a drift where the snow falls out the door and you'll save some work.

[DanO]

So from the info you guys gave me I can use a regular down

bag in a snow cave, that is if I am careful. This is good

as I like to save weight. I wonder if you guys have tips on

building snowcaves? I have read about various ways to build one.

I suppose I should go out and practice one weekend.

 

I have been eyeing those igloo building tools for some time

I think they are neat, would bring one for a denali trip. I am

not planing a denali trip anytime soon.

 

Thanks

Dan

Edited January 4, 2007 by DanO

[montypiton]

tips? - well, mattp just gave you a great one: wear as little as possible while you're digging, because whatever you're wearing will be soaked before the cave is finished. digging into a drift or wall allows you to tunnel upward from the door, which traps heat inside. practice caving is a great idea - dig a few close to the car and sleep in them before you commit yourself bigtime. be generous with interior space - seems like they always look big enough long before they really are. like anything else, a little practice goes a long way. After a couple of regular caves, try a "shovel-up" - which is a cave dug into snow you've piled up when the snow's not deep enough for caving. I've slept in shovel-ups with groups of six and more, with less than a foot of snow on flat ground...

[Ovr40]

I've had good luck using a Bibler/Black Diamond Winter Bivy to protect the sleeping bag. It's less than 10 ounces and very compact.

[jmckay]

Been quite awhile since I have done any of that kind of camping but i can remeber a few things fom the distant past. Most of which matt has pointed out to you.

 

1 Gor-tex and down- I had a winter bag that had such an outer shell but what I found was rather then the moisture getting in from the top it stayed in from bottom. Course some of these trips were a week or longer and you accumulate a lot of water in your clothing. the moisture seemed to recrystalze just below the gor membrane. these were a lot dryer climates then what you west coast newfies are used to. In the end I switched to a two bag syatem with a outer over bag collecting the moisture which I found easier to dry. The inner was stil down. i think the outer was that real light chiounard thingy.lighter down bag as my main bag.

 

2 curved roof on a snow cave but i was always so soaked by the end of digging one that I took up igloo building, They are not as hard as they look but then I am a Canadian half/breed so it may be in the jeans.

 

3 The cave seemed to get claustraphobic as most roofs seemed to sag after a few days (sometimes less). I accounted this to moisture gathering in the ceiling.

 

4 poor mans snow cave- If i was in a hurry and had a reasonable quarry i would dig a trench wide enough for two then wedge blocks in a triangle as a ceiling then shovel snow back over the ceiling. If yeh got no igloo jeans these might be easier.

 

5 Digging into the leaside- this has been mentioned but worth repeating. stay a bit drier. didn't do this on baffin once and found that the wind decided it wanted my to relocate my cave to Greenland

 

6 shovel the cieling into a nice smooth dome shape- Nothing more annoying them having water dripping down in the middle of the night. This when it seemed to happen to me, guess it took awhile for te ceiling to become saturated.

Edited January 4, 2007 by jmckay

[Bug]

As was said earlier, find the face of a drift or hill that is not about to slide with you in it. Dig straight in and then up.

When you are high enough that the floor of your cave will be higher than the top of your entrance, start digging sideways. This traps the warm air in the cave. If the top of the entrance is higher than the floor, it will be MUCH colder and drafty.

Put a high vent hole in a place that is not going to get buried by snowfall or blowing snow. Out the face you dug into works best. A ski-pole-basket size hole is perfect for me. Have the floor of the cave slope up a little bit so it will drain into the entrance. Dig small ditches around the outside edge. Smooth out the roof so you do not have dripping stelagtites. This is nearly impossible to get perfect. I love my goretex bivy bag and my 2lb Polarguard 3D bag for that reason. To each his own. I use a metal shovel. stick it straight into the snow and make a four-sided block. Pry it one way or another to get it to break off in the back. You may have to cut it in half or dig out one side to get it to break off. Hand it out to the person outside who can then make a wall to channel the wind. I like to sit outside the cave a lot. The inside is really nice for reading since the walls reflect all the light in every direction. Chop in some shelves for gear and stash. You can cook in there if you have good ventilation. I always make two extra high vent holes and plug them when I am through. Don't think about the fact that it could all collapse on you any second.

Bring a dog. If you don't have a dog, bring a girl-friend but they eat more, whine more, and you have to carry most of their gear.

Bites don't it?

[Couloir]

Great shots jmckay!

[mullster]

Yes, you need something betweeen you and the ground/snow/ice. Without a pad or bivy sack of some sort your basically sleeping on ice.

 

Whatever you do don't rely on your rope as a pad (ala Mark Twight "Fast and Light"). I did this once on a winter climb of Hood and is was one of the worst nights out I've ever experienced.

Invest in a nice pad, at least 3/4 lenght and then use your pack for the legs. You can also put your legs in the bag for more warmth.

[sexual_chocolate]

how hard would it be to build a snow fort without a shovel? do some of you out there think you'd be all right if you were stranded out there without a shovel?

[Couloir]

how hard would it be to build a snow fort without a shovel? do some of you out there think you'd be all right if you were stranded out there without a shovel?

I've done it. And it's not easy. If the snow is soft, forget using your adze. If the snow is hard, forget using your adze. You eventually end up using anything you have (helmet, pack stays, anything hard). It's usually very inefficient. Carry a METAL (not a plastic, which is fine for soft snow) shovel.

[Displaced Native]

I've stayed in a snow cave for six nights with two other people. We made a really heavy duty cave, taking our time. This was part of a NOLS course. For quick, expedient emergency shelter, I would seriously revamp what we did. However, for a base camp, it was awesome.

 

We stomped a platform about 12 feet in diameter, shape of a circle. We then scooped snow from outside the circle onto our platform into a dome about 5 feet tall, packing it with slaps from the shovels as we stacked it. We then let that set up for an hour. We stuck skis and poles all around the stacked dome about two feet in depth. It made the dome resemble a bristled porcipine..sorta. The idea being that as we hollowed the cave from the inside, when we hit a ski or pole, we knew we were about two feet thick at that point.

 

We then picked an aspect where we wanted our door. We chose an east view for the morning sun to help warm things up in the morning, but not bake us through the long part of the day. On the east side, we dug down at the edge of our platform approx 5 feet, in a crater about 8 feet long by 5 feet wide. We called this the "bomb crater" In the bomb crater, we sculpted counter tops, cabinets, shelves. This would be our kitchen.

 

Where the bottom of the bomb crater met the platform, we burrowed straight in about a body length. One person is the "mole", scooping snow behind themselves, the other two guys outside taking the snow, tossing it out of the bomb crater. Once he was about a body length into the dome, the mole starts to burrow upwards about a half of body length. From there, he starts to carve out the cave. This ensures that the cave has a higher floor than entrance, acting as a heat trap.

 

Dome shape on the inside is key to both drip control and for strength. We had six days of "baja beach days" in the Tetons. It felt like it hit 60 degrees in the sun every day. At the end of the week, we had six guys standing on top of the cave and no signs of failure. I qualify for the Clydesdale division of most competitions (fat body) and it took some serious jumping before we got it to break.

 

http://www.flickr.com/groups/52497336@N00/pool/ should be a link to some caves built on similiar NOLS trips.

 

Like I said..if you were in a pickle and time of the essence, I would seriously NOT follow that way of building. However, if I was pinned in for a few days and had nothing but time, I would remodel anything I slapped together in a hurry.

 

You do get wet. You're working so hard that wearing just your shell gear makes good sense. You won't be cold.

 

We used a ski to drill two vent holes..just twisting the ski as we pushed it through.

 

Steve

[jmckay]

Here is some thing that you do not see everyday. The last couple days the park wardens have been digging out a couple bodies from a collapsed snow shelter. Personally this is a first for me though Lisa say's ? she has heard of this before.

 

I have woken up with the roof being 3 inches away from my perfect roman nose. The night before it was 18 inches away. This is the first time that I have heard of anyone dieing in a collapsed snow cave

been there done that

Mckay

[mattp]

Whoa! That's kinda scary.

 

I've seen huge settling when the snowdrifts we dug into were not very old, in warm weather, and when we once had nine people and four stoves in a single snowcave.

[Cobra_Commander]

some folks like to wear their beacons when digging in a big drift

[Bug]

Bummer.

It would be interesting and perhaps life saving to get more details.