Emergency shelter in snow

Snow trench, quinzhee, snow cave or bivouac with bivy bag/tarp – what fits when a night in snow is unavoidable?

The four options differ greatly in effort, protection and risk. The comparison is qualitative and does not replace training. Two questions come before any choice: Can I turn back or reach a hut or vehicle? And am I safely outside avalanche terrain?

Starting situation

Legend
Method	Quick to set up	Wind and cold protection	Low collapse/burial risk	Staying dry while building	Possible with little snow	Manageable without much practice
Covered snow trench	Partly	Partly	Yes	Partly	Partly	Partly
Quinzhee (hollowed snow mound)	No	Yes	No	No	Yes	No
Snow cave in a drift	No	Yes	No	No	No	No
Emergency bivouac with blanket, bivvy bag or bin bag	Yes	Depends	Yes	Yes	Yes	Yes

Legend:● Yes◐ Partly◇ Depends○ No* = note available

Covered snow trench

Effort:: Usually up to about an hour with a shovel
Needs:: Shovel, sheet or snow blocks, sleeping pad

Quick to set upPartly
Quicker than cave and quinzhee, slower than a bivouac.
Wind and cold protectionPartly
Well out of the wind; a sheet roof is colder than snow.
Low collapse/burial riskYes
Minor consequences with a sheet roof; a snow-block roof needs more care.
Staying dry while buildingPartly
Digging makes you wet, but for less time than with cave builds.
Possible with little snowPartly
Needs some snow depth or firm snow.
Manageable without much practicePartly
Simplest snow shelter, practice still recommended.

Open guide →

Quinzhee (hollowed snow mound)

Effort:: Several hours including settling time
Needs:: Shovel(s), thickness markers, at least two people

Quick to set upNo
Piling, settling and hollowing take a lot of time.
Wind and cold protectionYes
Snow all around, very sheltered from wind.
Low collapse/burial riskNo
Collapse possible, especially with a thin roof or thaw.
Staying dry while buildingNo
Long work in snow, high risk of getting soaked.
Possible with little snowYes
Main advantage: snow is piled up.
Manageable without much practiceNo
Only after practice and never alone.

Open guide →

Snow cave in a drift

Effort:: Several hours
Needs:: A very deep drift in safe terrain, shovel, training, second person

Quick to set upNo
Very time-consuming.
Wind and cold protectionYes
Best insulation of the snow shelters.
Low collapse/burial riskNo
Collapse and avalanche danger on slopes.
Staying dry while buildingNo
A lot of work in snow.
Possible with little snowNo
Needs very deep snow.
Manageable without much practiceNo
Training including avalanche knowledge required.

Open guide →

Emergency bivouac with blanket, bivvy bag or bin bag

Effort:: A few minutes
Needs:: Bivy bag, emergency blanket or tarp; sleeping pad; shelter from wind

Quick to set upYes
Ready immediately.
Wind and cold protectionDepends
Strongly depends on wind shelter, sleeping bag and insulation.
Low collapse/burial riskYes
No load-bearing snow structure.
Staying dry while buildingYes
No digging needed; watch for condensation inside.
Possible with little snowYes
Independent of snow depth.
Manageable without much practiceYes
Little prior knowledge needed; keep the face uncovered.

Open guide →