If you are in a wooded area and have enough natural materials, you can make a field-expedient lean-to (Figure 5-9) without the aid of tools or with only a knife. It takes longer to make this type of shelter than it does to make other types, but it will protect you from the elements.
You will need two trees (or upright poles) about 2 meters apart; one pole about 2 meters long and 2.5 centimeters in diameter; five to eight poles about 3 meters long and 2.5 centimeters in diameter for beams; cord or vines for securing the horizontal support to the trees; and other poles, saplings, or vines to crisscross the beams.
Tie the 2-meter pole to the two trees at waist to chest height. This is the horizontal support. If a standing tree is not available, construct a biped using Y-shaped sticks or two tripods.
Place one end of the beams (3-meter poles) on one side of the horizontal support. As with all lean-to type shelters, be sure to place the lean-to's backside into the wind.
Crisscross saplings or vines on the beams.
Cover the framework with brush, leaves, pine needles, or grass, starting at the bottom and working your way up like shingling.
Place straw, leaves, pine needles, or grass inside the shelter for bedding.
In cold weather, add to your lean-to's comfort by building a fire reflector wall (Figure 5-9). Drive four 1.5-meter-long stakes into the ground to support the wall. Stack green logs on top of one another between the support stakes. Form two rows of stacked logs to create an inner space within the wall that you can fill with dirt. This action not only strengthens the wall but makes it more heat reflective. Bind the top of the support stakes so that the green logs and dirt will stay in place.
With just a little more effort you can have a drying rack. Cut a few 2-centimeter-diameter poles (length depends on the distance between the lean-to's horizontal support and the top of the fire reflector wall). Lay one end of the poles on the lean-to support and the other end on top of the reflector wall. Place and tie into place smaller sticks across these poles. You now have a place to dry clothes, meat, or fish.
In a marsh or swamp, or any area with standing water or continually wet ground, the swamp bed (Figure 5-10) keeps you out of the water. When selecting such a site, consider the weather, wind, tides, and available materials.
To make a swamp bed--
Look for four trees clustered in a rectangle, or cut four poles (bamboo is ideal) and drive them firmly into the ground so they form a rectangle. They should be far enough apart and strong enough to support your height and weight, to include equipment.
Cut two poles that span the width of the rectangle. They, too, must be strong enough to support your weight.
Secure these two poles to the trees (or poles). Be sure they are high enough above the ground or water to allow for tides and high water.
Cover the top of the bed frame with broad leaves or grass to form a soft sleeping surface.
Build a fire pad by laying clay, silt, or mud on one comer of the swamp bed and allow it to dry.
Another shelter designed to get you above and out of the water or wet ground uses the same rectangular configuration as the swamp bed. You very simply lay sticks and branches lengthwise on the inside of the trees (or poles) until there is enough material to raise the sleeping surface above the water level.
Do not overlook natural formations that provide shelter. Examples are caves, rocky crevices, clumps of bushes, small depressions, large rocks on leeward sides of hills, large trees with low-hanging limbs, and fallen trees with thick branches. However, when selecting a natural formation--
Stay away from low ground such as ravines, narrow valleys, or creek beds. Low areas collect the heavy cold air at night and are therefore colder than the surrounding high ground. Thick, brushy, low ground also harbors more insects.
Check for poisonous snakes, ticks, mites, scorpions, and stinging ants.
Look for loose rocks, dead limbs, coconuts, or other natural growth than could fall on your shelter.
For warmth and ease of construction, this shelter is one of the best. When shelter is essential to survival, build this shelter.
To make a debris hut (Figure 5-11)--
Build it by making a tripod with two short stakes and a long ridgepole or by placing one end of a long ridgepole on top of a sturdy base.
Secure the ridgepole (pole running the length of the shelter) using the tripod method or by anchoring it to a tree at about waist height.
Prop large sticks along both sides of the ridgepole to create a wedge-shaped ribbing effect. Ensure the ribbing is wide enough to accommodate your body and steep enough to shed moisture.
Place finer sticks and brush crosswise on the ribbing. These form a latticework that will keep the insulating material (grass, pine needles, leaves) from falling through the ribbing into the sleeping area.
Add light, dry, if possible, soft debris over the ribbing until the insulating material is at least 1 meter thick--the thicker the better.
Place a 30-centimeter layer of insulating material inside the shelter.
At the entrance, pile insulating material that you can drag to you once inside the shelter to close the entrance or build a door.
As a final step in constructing this shelter, add shingling material or branches on top of the debris layer to prevent the insulating material from blowing away in a storm.
Tree-Pit Snow Shelter
If you are in a cold, snow-covered area where evergreen trees grow and you have a digging tool, you can make a tree-pit shelter (Figure 5-12).
To make this shelter--
Find a tree with bushy branches that provides overhead cover.
Dig out the snow around the tree trunk until you reach the depth and diameter you desire, or until you reach the ground.
Pack the snow around the top and the inside of the hole to provide support.
Find and cut other evergreen boughs. Place them over the top of the pit to give you additional overhead cover. Place evergreen boughs in the bottom of the pit for insulation.
See Chapter 15 for other arctic or cold weather shelters.
Beach Shade Shelter
This shelter protects you from the sun, wind, rain, and heat. It is easy to make using natural materials.
To make this shelter (Figure 5-13)--
Find and collect driftwood or other natural material to use as support beams and as a digging tool.
Select a site that is above the high water mark.
Scrape or dig out a trench running north to south so that it receives the least amount of sunlight. Make the trench long and wide enough for you to lie down comfortably.
Mound soil on three sides of the trench. The higher the mound, the more space inside the shelter.
Lay support beams (driftwood or other natural material) that span the trench on top of the mound to form the framework for a roof.
Enlarge the shelter's entrance by digging out more sand in front of it.
Use natural materials such as grass or leaves to form a bed inside the shelter.
In an arid environment, consider the time, effort, and material needed to make a shelter. If you have material such as a poncho, canvas, or a parachute, use it along with such terrain features as rock outcropping, mounds of sand, or a depression between dunes or rocks to make your shelter.
Using rock outcroppings--
Anchor one end of your poncho (canvas, parachute, or other material) on the edge of the outcrop using rocks or other weights.
Extend and anchor the other end of the poncho so it provides the best possible shade.
In a sandy area--
Build a mound of sand or use the side of a sand dune for one side of the shelter.
Anchor one end of the material on top of the mound using sand or other weights.
Extend and anchor the other end of the material so it provides the best possible shade.
Note: If you have enough material, fold it in half and form a 30-centimeter to 45-centimeter airspace between the two halves. This airspace will reduce the temperature under the shelter.
A belowground shelter (Figure 5-14) can reduce the midday heat as much as 16 to 22 degrees C (30 to 40 degrees F). Building it, however, requires more time and effort than for other shelters. Since your physical effort will make you sweat more and increase dehydration, construct it before the heat of the day.
To make this shelter--
Find a low spot or depression between dunes or rocks. If necessary, dig a trench 45 to 60 centimeters deep and long and wide enough for you to lie in comfortably.
Pile the sand you take from the trench to form a mound around three sides.
On the open end of the trench, dig out more sand so you can get in and out of your shelter easily.
Cover the trench with your material.
Secure the material in place using sand, rocks, or other weights.
If you have extra material, you can further decrease the midday temperature in the trench by securing the material 30 to 45 centimeters above the other cover. This layering of the material will reduce the inside temperature 11 to 22 degrees C (20 to 40 degrees F).
Another type of belowground shade shelter is of similar construction, except all sides are open to air currents and circulation. For maximum protection, you need a minimum of two layers of parachute material (Figure 5-15). White is the best color to reflect heat; the innermost layer should be of darker material.