This weekend I took students out to experience what it’s like to live in a debris shelter for a night, while it was 5 degrees fahrenheit outside.
It seems pretty simple to build a shelter out of debris. Pile up a bunch of leaves and dig in! But unless you do it right, it’s about as warm as a paper bag. One out of 7 students were able to stay the entire night without a sleeping bag.
What did the successful student do differently? Read on…
How it works
The key to a good debris shelter is insulation or “dead air space”. If the air is able to move, it will do so via convection, moving away from your warm body as cold air moves in to take its’ place. You need to be packed tight!
A debris shelter can be at its’ most simple, a pile of leaves, straw, or whatever will hold “dead air”. The problems with the pile method is that you can’t get it packed as tight, and as you move around while sleeping the debris will fall away from you, especially your upper body and head.
As you may know, your head will always lose heat, because our brains need the warm blood supply, while our extremities will close off blood flow to keep the core of your body normothermic, or at the temperature it works best at, around 98.6
How to build it
Start by finding a good location. You’ll want dry ground with lots of debris around that is easy to “rake” up with your hands. This is key. Find a tree with a crook at about navel height, or you can find two forked sticks to hold up the ridge pole so don’t pick your spot based on constructing the frame. This is the easy part.
Start by laying down on the ground to see where you want the shelter to be. Then lay out sticks to surround your body roughly 6-8″ from your silouette. This is your frame stick spacing and you will need this space to pack insulation INSIDE the shelter later on.
Now find a ridge pole. It will need to be around 12′ long, but you can improvise. The idea is to support your ridge pole from your head area, at around the height of your navel while standing up at the entrance. (see photo) The other end of the ridge pole slopes downward towards your feet until it hits the ground.
Build the frame
Next, lean sticks onto the ridge pole, making sure to break them just long enough to meet the ridge, and not extend way past it. The bottom end rests on or just outside your body pattern that you laid out. Lay sticks next to one another, with 2-4″ space between each, all the way from your toes, to 1-2′ past where your head will be.
Lay the covering
If you’re lucky, there will be lots of bark lying around that you can shingle your new house with. Look for dead trees where the bark is falling off by itself. Birch, Cottonwood, Basswood all work well. If you don’t have bark, you’ll need to pile debris on top. Make sure to save your best debris for the inside. The outside/top debris can be anything from wet leaves to moss, dirt, etc. You just need to make a strong, waterproof container to fit your inside insulation in to. Pile this elbow to should deep, depending upon the season. You can test it by shoving your arm through the debris to the frame. If the debris comes to your armpit, you for sure have enough. (though it will settle over time)
Yup. Find a way to gather as much dry, soft material as you can, and stuff it in. You’ll need to intermittently crawl inside to stuff the end where your feet will be. Keep crawling in and out until your insulation is packed so tight that when you crawl out your last time, the insulation leaves a hole where you came from. If it drops down to the bottom you don’t yet have enough insulation. Go out and get more! It will be worth it for a good night’s sleep.
A debris shelter will keep you warm in any weather or temperature. It takes practice, trial, and error to get it right.