What Is a Snow Cave?
Due to the presence of air pockets, snow qualifies as a top-notch insulator. The insulation attribute of snow is ingeniously harnessed in the construction of snow caves, resulting in a cozy abode. A well-planned snow cave design is instrumental in retaining body heat, obstructing wind, averting moisture buildup, and ensuring an adequate oxygen supply.
5 Types of Snow Shelters
The selection of an appropriate snow shelter that suits your requirements is dependent on various factors such as the climate, the amount of time and effort you can devote, and the equipment you possess. You may take into account the following categories of snow shelters:
- 1. Snow trench: A snow trench can be an excellent, quick means of survival in harsh weather conditions. Use a shovel or simple digging implement to carve out a rectangular space a few feet deep that you can lie down in. A snow trench will keep you out of the wind. You can stretch a tarp over the top to help trap body heat in the trench.
- 2. Tree pit: One of the simplest kinds of snow shelters is a tree pit. In areas of sufficiently deep snow, it can be possible to slowly dig out a space around the trunk of an evergreen tree, reaching from the ground to the lowest level of branches. Insulate the bottom with evergreen boughs, pack the walls to strengthen them, and use other evergreen boughs to cover the top and keep the heat in.
- 3. Snow cave: To make a snow cave, you’ll need a large snowdrift—large, wind-driven masses of snow are best. Slowly tunnel into the drift, starting low and working your way up. The main shelter space should be bell-shaped for strength and higher than the entrance tunnel to keep the heat in and let cold air out. Pack the inside of the tunnel and space gently but firmly as you go. It is helpful to have a snow saw and shovel for building a snow cave.
- 4. Quinzhee: Quinzhee is a sturdy, medium-long-term snow shelter for winter camping. (“Quinzhee”, also spelled “quinzee,” is an Athabaskan word, a native language group in North America.) It is simple to construct a quinzhee with basic digging implements, if somewhat labor-intensive. Shovel snow into a big pile or mound. (The exterior dimensions for a few inhabitants are about ten feet in diameter and five feet in height.) The snow mound should sit for at least a couple hours; this process, called sintering, allows the snow to compress and solidify. Then, carefully scoop out a short entranceway and the dome-shaped interior, with a small hole for ventilation near the top. Use some of the scooped-out snow to make a shallow sleep platform.
- 5. Igloo: The Igloo is the best choice for a longer-term winter shelter. An igloo is built from cut blocks of wind-driven snow and can last for months in the cold seasons of high-latitude climates. Lay the snow blocks spirally to provide sturdy, insulating walls. Scrape the insides smoothly to strengthen the structure and prevent the accumulation of condensation.
How Do Snow Shelters Keep You Warm?
When the outside temperature drops to thirty-nine degrees Fahrenheit (four degrees Celsius) or below, it is feasible to feel quite at ease inside a snow shelter that has been constructed well with walls that are a minimum of twelve inches thick. The shelter can be warmed up with only body heat as the energy source, and although it is not cozy, it can still be livable if the occupants wear warm clothing or utilize sleeping bags.
Design Characteristics of a Snow Cave
What sets snow cave shelters apart from other winter survival shelters are these distinctive features.
1. Requires Large Amounts of Snow
If there is not enough snow with a depth of at least 4-5 feet, it is advisable to construct a shelter from debris rather than attempting to create a snow cave by digging straight into the snow.
2. Thick Walls and Roof
For a snow cave to be structurally sound, it is necessary to have walls and roof that are at least 1 foot thick, as anything thinner than this could result in instability, leading to the collapse of your snow cave.
3. Roof Is in a Dome Shape
When using a winter shelter, it is common for condensation to accumulate on both the roof and walls. To prevent direct dripping on oneself, using a dome-shaped shelter instead of a cube-shaped shelter allows the condensation to slide down the walls.
4. Entrance Tunnel Is Located Below the Main Shelter
This design characteristic offers two advantages. First, it prevents wind from entering the cave by keeping the entrance low. Second, as heat tends to rise, this feature also aids in retaining heat within the primary shelter.
The crew of the Washington State Department of Transportation constructed this cave to shield themselves from the wind while working. Although it provides some protection from the elements, the design of the cave is not very effective at retaining warmth since its entrance is on the same level as the chamber.
Snow Cave vs. Igloo
A snow cave and an igloo share many similarities, but the key variation lies in the fact that the latter is constructed out of pre-cut snow blocks that are packed tightly together. Only high-quality snow is required for the creation of an igloo, and constructing one entails a significant amount of effort. These structures are designed to be semi-permanent shelters.
By contrast, snow caves are dug directly into the snow. They are not meant to be a permanent shelter but rather an emergency or short-term shelter.
Snow Cave vs. Quinzee
A quinzee is commonly recognized as a variation of a snow cave, created by constructing a big heap of snow, compacting it, and carving out a cave within it. Nonetheless, a quinzee is crafted when the snow doesn’t have sufficient height to permit direct excavation of the cave. The opening tunnel is situated at an equal elevation to the primary area, so a quinzee lacks the same level of warmth as a snow cave.
How to Make a Snow Cave
Unless you are a park ranger, mountaineer, or engage in extreme winter sports, the likelihood of encountering a scenario where you require building a shelter for survival in a snow cave is negligible. Nonetheless, learning how to construct a snow cave is an advantageous skill and an enjoyable exercise.
This is the way to do it.
Equipment Required:
- Shovel: Plastic shovels are out! You will need a sturdy shovel, preferably an avalanche shovel like this one on Amazon.
- Saw: A saw makes it much easier and faster to cut out large blocks of snow
- Ski pole: Or other long pole for poking air vents
Duration:
Making a snow cave can take over 4 hours despite having experience. The process involves extensive physical exertion as one has to crawl and crouch. Having a partner can be beneficial so that one person can dig while the other removes snow.
Step 1: Find the Right Site
To make things easier and more secure, it’s important to locate the appropriate spot for your snow cave. Seek out an inclined surface, like a hill, that is covered in snow. This will enable you to dig upwards while constructing the entryway tunnel, as the snow is inclined. Additionally, due to the incline, snow will naturally cascade downhill as you dig.
To remain secure:
- Avoid cornices: These are mounds of snow that build up on and overhang mountain edges. Do not dig into snow cornice, or it could collapse. Don’t build underneath a cornice either.
- Avoid potential avalanche sites: Here’s avalanche info from the NWS
- Watch out for “widow-maker” trees: These are dead trees or limbs which could fall on your cave.
2. Pack Down the Snow
In case the snow in your preferred cave-building location is loose and powdery, it would not offer a strong foundation, thereby risking the cave’s collapse on you. Make sure to compact the snow by trampling it with your boots or snowshoes.
3. Dig the Entrance Tunnel
When constructing a snow cave on a slope, beginning the digging process in an uphill direction is recommended. However, for building on level ground, it is advised to dig down to the ground level or multiple feet down before digging inwards. The objective is to maintain a safe and stable structure.
It is recommended that the entrance tunnel be:
- Dome-shaped
- Approximately 3 feet high
- 1-2 feet wider than your body
4. Excavate the Cave Space
After excavating a 3 to 5 feet long entryway, you may proceed with the upward digging process which marks the start of forming the snow cave.
It is important to start shaping the ceiling of the snow cave first while ensuring it remains in a dome or bell shape. Shaping the walls or floor beforehand could result in the cave collapsing on you. Keeping a dome shape maintains the stability of the structure.
It is important to avoid enlarging the snow cave more than required to preserve body heat, as a smaller one will retain it more effectively.
5. Keep Walls Thick
For a snow cave to offer adequate insulation and avoid collapse, it is necessary for its walls to be a minimum of one foot thick. Thinner walls will not be sufficient.
Typically, it is advised to cease digging when you can observe light coming through the snow. To serve as indicators, some individuals insert sticks one foot deep into the edges of the snowdrift. Upon encountering these sticks, the digger should halt excavation.
6. Create a Heat Sink
Snow caves are effective because the sleeping platforms draw warm air upwards. Another location for cold air to descend is created by excavating a hole in the central chamber.
In order to achieve this objective, snow caves made for two individuals typically take on a T-shape design (as illustrated in the picture beneath). The T’s midpoint functions as a heat sink, while the raised-bed platforms on either side are topped with a dome-shaped ceiling.
7. Smooth the Ceiling
To ensure winter survival, it is essential to have a smooth ceiling in a snow cave. As the heat from your body melts the snow inside, any uneven or projecting areas on the ceiling will lead to dripping water on you. Therefore, staying dry is crucial.
8. Make Air Vents
To create air flow within the snow cave, it is necessary to create holes in the ceiling using either a ski pole, trekking pole, or a long stick.
Leaving one ski pole sticking out through the ceiling can serve as an emergency air hole in case the air vents become blocked due to snowfall or high winds.
9. Set Roof Support
In the event of a collapse of a snow cave during sleep, it is possible to become trapped beneath a cover of snow with no means of escape. To safeguard against this possibility, it is advisable to erect a hiking pole or any similar object upright near your head. This will serve to puncture the snow ceiling should the cave collapse, providing you with an air pocket. The pole may also be utilized for digging one’s way out.
10. Mark the Cave Location
To avoid getting lost in the snow, mark the entrance and roof area of the snow cave. Using ski poles with a vividly colored bandana attached to them is an effective way to create markers.
An additional concern is the risk of your snow cave collapsing if you step onto its roof. To avoid this, it is advisable to place extra markers beyond the entrance of the cave to ensure that you do not venture too close.
11. Using the Snow Cave
- Block the entrance with snow: This will keep wind out.
- Keep your shovel in the shelter: In case you need to dig your way out.
- Make your bed: If you don’t have a sleeping pad, gather pine boughs to serve as a bed. You can sleep on top of your bag and gear for extra insulation.
- Clear ice which forms on the walls or ceiling of the snow cave : The ice reduces ventilation and can cause you to suffocate in the shelter.
- Keep gear away from the sides of the cave: Melting snow will drench it.
- Light a candle : A candle lantern like the UCO can add a surprising amount of heat to the cave.
