The goal of all survival shelters is to keep you dry and at a comfortable temperature. This means they should be as weather-proof and insulated as possible. Knowing how to build the following structures can help you survive emergencies in almost any wilderness environment.
The easiest and most basic structure to build from scratch is a lean-to. It keeps the rain off, but provides little-to-no heat retention since it’s open on three sides. For a single person, build a stick framework roughly 5 feet high by 7 feet long and prop it up at a 45-degree angle with stout posts. Orient the back to the prevailing wind.
An A-frame shelter is open on two sides providing better heat retention and protection from the elements than a lean-to, but takes twice as long to make. However, by securing a tarp over a line stretched between two trees, an A-frame shelter can be built in minutes.
Despite its ability to mitigate temperature extremes (thermal mass), soil is a poor insulator. It can drain heat from the body surprisingly quickly. Conserve energy by placing insulation between you and the ground. Tree branches, grass clippings, moss and even snow make excellent improvised insulation.
To build a raised platform, anchor four posts into the ground, lashing supports to the uprights. Layer 1-inch diameter poles, then green foliage over the horizontal supports to create a (relatively) comfortable bed.
If the ground is damp or you think flooding might an issue, always, always, always build a shelter with a raised sleeping platform. Moisture draws heat from the body exceptionally fast. If you allow your core temperature to drop just a few degrees (below 95 F), you can die. On average, hypothermia kills over 600 people in America every year. Keep your shelter dry.
In fact, the only time to bed down directly on the ground is in extremely hot climates to prevent dehydration.
Underground shelters provide relief from the extreme heat of desert climates.
To build an underground survival shelter, dig a trench deep enough to lay down in, then stretch a tarp over it to provide shade. If possible, secure another tarp over the first one, leaving a 6-8 inch air gap to better insulate you from the sun. Digging just a few feet down can drop temperatures by 30 degrees F or more.
Unless you find a pre-dug pit or cave, building an underground survival shelter takes lots of work. Be sure to gather plenty of food and water before building.
But if it’s your last resort and must use a cave, never strike a match anywhere near it. A camp fire can quickly burn all the oxygen and if your cave hosts a bustling community of bats, the gas from their guano can ignite, causing an explosion. Though why you’d want to lie in bat shit in the first place is beyond me.
Click here to learn more about building a dirt-cheap permanent underground survival shelter.
To build an igloo, saw out rectangular chunks of snow, placing them in a circular pattern at least 8 feet in diameter. To enclose the structure, taper the blocks so they angle inward, or simply offset them so each course has a smaller diameter than the last (called the ‘Corbel effect’). Position the blocks in a running bond, like in a brick wall, for strength. Once the last block is in place, pack the entire structure with snow.
When building completely-enclosed survival shelters, remember to include air holes. (That whole suffocation thing again.) Because cold air sinks, the air intake, often the shelter entrance, should be lower than the sleeping and working platforms. Position the exhaust air hole above the entrance, near the top of the structure.