So, Are Snow Caves Hot or Cold?

Snow caves are a time-tested shelter option for anyone hiking or surviving in frigid and snowy environments.

Unique among most emergency and improvised primitive shelters, a snow cave is not so much built as it is excavated from a deep drift or steep bank of snow.

These shelters are renowned for their insulating and protective capability, keeping the occupants drastically warmer than they would be out in the open air.

But, certain sources of prepper lore have indicated that snow caves can actually become quite warm on the inside. Is this true?

Are snow caves hot or cold inside? Any snow cave is going to be cold inside. An average snow cave in freezing conditions will maintain an internal air temperature of about 32° F(0° C) with human occupants inside. Even when outside temperatures plunge to well below zero, the interior of a snow cave will be far more survivable. 

You might think this is one of the more obvious questions concerning survival trivia we have answered on this site, but there is actually a bit more to learn about snow caves, and some of it might surprise you. Keep reading to learn more.

What is a Snow Cave Exactly?

A snow cave is a survival shelter that is exactly as the name describes. A cave made from, or rather excavated from, the snow.

Snow caves are dug into deep drifts of snow, or into a thick layer of snow that has accumulated on a hillside.

Consisting of a short entrance tunnel leading to a small chamber with benches on either side to allow occupants to sit or lay down, a snow cave is capped with a domed roof that provides adequate strength to support the weight of the snow above it.

Snow caves sound simple, and they are in theory, but careful attention to detail is needed to maximize the design.

For instance, the entrance tunnel should be only wide enough to permit occupants to enter and exit as this will help trap heat inside the snow cave.

The entrance tunnel itself should be long enough to help defeat wind outside the cave and additionally a short trench or shallow pit can be dug in the middle of the chamber in order to allow cold air to settle into it, keeping the occupants above it on the benches warmer.

Lastly, the chamber itself should be dug on a slight incline above the entrance.

Since hot air rises and cold air settles this will again help trap warmer air inside the chamber while allowing cooler air to seep out.

It is no wonder that cultures around the world and even animals have made use of snow caves for millennia and they remain in use today even among professional explorers and scientists since they are comparatively easy to set up with minimal tools.

Duh! It’s made of snow, how could it be warm?

You’re quite correct, reader. Snow caves are constructed solely from snow and since snow is itself quite cold and can only form in cold conditions it seems entirely obvious that a snow cave would be cold.

Because of course it would, right? Right, except that cold in this case is a relative term.

Snow caves are so beloved by cold-weather adventurers and outdoorsmen because they are fantastically insulating, against both ambient temperature and wind alike.

How can this be?

Simple: The packed snow that forms the tunnel, walls, and roof of the snow cave is impermeable enough to keep out wind and insulating enough to trap the majority of air inside the chamber.

This air is readily warmed by human bodies and can be further warmed by the use of a camp stove or a very small fire.

This easily allows the internal temperature of the snow cave to stay right around freezing temperature, or 32° F (0° C).

You are probably thinking that sounds quite cool, literally, and you are right but the remarkable thing is that a snow cave can maintain this temperature even when outside temperatures are more than 40° F (4° C) below zero with howling gusts of wind in the bargain!

Considering that that is a temperature spread of over 70° F(21° C) and the temperatures outside the snow cave are positively lethal, I’d say that is pretty damn remarkable, wouldn’t you?

What’s the Catch?

There’s no catch, not really, so long as someone that pays attention to properly constructing the snow cave and knows what they are doing to ensure that it will be sturdy and safe.

That being said, like any improvised shelter employed in a hostile environment there are risks involved, and a few more risks are inherent to snow caves than other types of shelter.

First, collapse will always be an issue and anything that falls or anyone who walks over the roof of the almost perfectly camouflaged snow cave will collapse it. This could potentially trap the occupants within.

Second, the humidity generated by perspiration and respiration from the occupants can result in icing forming on the interior walls and roof of the chamber, slowing the passage of air.

If the entrance tunnel should become blocked with snow or some other obstruction asphyxiation is a possibility.

Experienced snow cave users typically employ dedicated ventilation or air holes for this purpose.

Lastly, though a snow cave is extremely appealing as a last-ditch emergency shelter since it requires no real assembly, only excavation, it should still only be dug with tools as digging it by hand will be both highly strenuous and drastically increase the risk of frostbite of the fingers and hands.

Even with gloves on, it won’t be enough to keep out that kind of cold for the few hours it will take to excavate the cave.

Maximizing Shelter Provided by Snow Caves

You won’t be able to sit around a snow cave in basic pants and shirt and keep warm, as you’ll still be experiencing frozen temperatures.

However, so long as you are dressed appropriately for winter weather and have access to a sleeping pad, sleeping bag, and blankets you should be quite comfortable inside as long as you’ve constructed the chamber properly.

A well-outfitted snow cave chamber will have long benches that are the same height as the occupants cut out of the side walls or at the minimum built up off the floor at least a foot.

Upon these benches the occupants may sit or lie down, and with an insulating pad between them and the snow upon which they may place their sleeping bags before snuggling into them while wearing their clothes they can remain remarkably warm and comfortable.

Additional improvements to the comfort of the interior can be had by installing a right angle or zigzag baffle outside the entrance to help block the wind and digging or cutting a trench or pit in the center of the floor.

This will, as mentioned, allow cold air to sink and also make it safer to utilize a small camp stoves or tiny fire inside.

Be warned, as it is easy to go overboard and raise the temperature too much inside, potentially weakening the structure of the cave.

Also, any internal or nearby sources of combustion must be properly vented inside the snow cave to prevent carbon monoxide buildup and subsequent poisoning.

This is statistically one of the biggest dangers that users of snow caves incur on a regular basis.

Conclusion

Snow caves are extraordinarily effective and efficient survival shelters in cold, wintry environments, but contrary to the opinions of some, the interiors are in no way what could be described as warm, only warmer compared to the outside environment.

Nonetheless, a snow cave is an excellent way to stay alive when outside temperatures plummet.