Shelter Construction

Written by Roger Perron and David R. Reed

You will need to make fire and to choose the right type of fire construction. Shelter is necessary to give shade, to repel wind, rain and to keep warmth. Sleep and adequate rest are essential and the time and the effort you put into making your shelter comfortable will make them easier to get. If you are a victim of a plane crash or a vehicle that has let you down, it may provide a shelter or materials which one can be built, but if there is a fire or the threat of fuel tanks exploding, wait until it has burned out before attempting salvage.

You may have to make do with any natural shelter that you can find for the night or until you can fully assess the situation. In this case, virtually any protection from wind, rain & cold will be welcome. If movement down a slope seems risky, traversing even a short way along the contour may bring you out of the wind. If no cave or crevice is available to give shelter, make use of any hollow in the ground. Add to its height, if you can, by stacking rocks or snow, but make sure that any structure is stable & use a back-pack, if you have one, to increase the windshield before settling down on the leeward side.

For a long-term camp you should find a secure site with convenient access to your major needs. Look for these when selecting your campsite:

Wind sheltered
Offer wood for burning
Away from swamp, dampness.
Close to drinking water supply yet not too close bugs.
Seek Dry ground as much as possible.
High enough to AVOID mosquitoes using air draft.
Shelter opening facing east or rising sun position.
Winter: Sheltered from wind as much as possible.
Winter storms ALWAYS come from the West & North.

Other considerations for a long-term shelter:

Hilltops exposed to wind, move down and look for shelter on the Leeside.
Valley bottoms and deep hollows - could be damp & especially when the sky is clear, more liable to frost at night.
Hillside terraces where the ground holds moisture.
Spurs which lead down to water, which are often routes to watering places for animals.
Look for somewhere sheltered from the wind, on rising ground that has no risk of flooding and is safe from rock falls or avalanches.
Hot air rises, cold air sinks, so valley bottoms will often pockets of cold air and in cold weather, be susceptible to frost and damp mist.
In areas that get plenty of rainfall, terraces across a slope will often be damper than the steeper ground above and below them, for water collects there before flowing further downward.

Pitching camp too close to water, however may lead you to be troubled by insects and the sound of running water can hide other noises that might indicate danger or the sound of search or rescue parties. (Sniper Note: Camping next to water will keep animals that depend on the water for their survival from approaching. Be courteous to the natural habitants when near small ponds or in any area with a scarce water supply.) Near riverbanks, look for the high water mark. Also near sea where there are tidal changes.

In MOUNTAIN REGIONS streams can become torrents in minutes, rising as much as 5m (17ft) in an hour! Even on plains keep out of old watercourses, no matter how dry they are. Heavy rainstorms in nearby hills can easily send water rushing down them in flash floods with no warning. Choose ground that is reasonably flat and free or rocks and insure that you have space to lay out signals and that you can be easily spotted by rescue parties. Check above your head for bees or hornets' nests and for dead wood in trees that could come crashing down in the next storm or high wind. Keep away from solitary trees, which attract lightning, and in forest areas keep to the edges where you can see what is going on around you.

Don't wait until it's dark. Make or find a shelter while there is light. You must get out of the rain, wind, and snow before Hypothermia sets in. Make more permanent shelter when permitted. Insulate floor of shelter as deeply as you can with brush, leaves, and grass- anything to keep you off the cold ground.

Dig tunnel into snow if no other shelter is available. Use stick to keep air vent open. In deep snow, base of trees can provide shelter. Use your imagination, improvise but keep shelter simple and small, conserve energy. You will get cold faster if you lay on the bare ground, make a bed of something. Be careful about staying near steep slopes or cliffs. Slides and avalanches are a danger.

The following are essential for shelter:

Insulated bed
Wind Blocker
Small as can be squeezed into - conserves heat

How long do you intend to remain at the location? Snow caves and natural holes are ideal if you are on the move and do not need a permanent structure. Size will depend upon the number in the party. Sleep with your head elevated, head lower than feet can cause headaches. Tall grass is where the chiggers, ticks and other bugs like to camp too. Alpine meadows are fragile. Camping there for a week may leave a visible scar for years.

All shelters must be ventilated for evaporation. Fires give off carbon monoxide. Heat up stones, wrap them well, and insert them in your sleeping bag. Old trapper trick: Dig a rectangular hole, fill it with hot coals, then cover up with earth and lay a blanket over it.

Mosquitoes seem to hate the smell of Basilic.

A heavy grove of big evergreen itself affords considerable shelter. From sudden shower you can keep dry by just lingering under a spruce or pine. There is usually sufficient small growth in such a forest to break off and angle in lean-to form against a protective log or trunk. Build a lean-to with whatever is available. All you need is a cross bar between two supports. Lean branches densely against the cross bar to make the shelter. If you have enough plastic groundsheet material, fold it so that it doubles as groundsheet and a roof. Then pile on branches and leaves/snow.

At very low temperatures snow will be solid. You need some kind of implement to cut into it or make blocks from it. If you have tools to cut blocks of snow, you can build a complete snow house or use it for walls around another shelter.

Snow or rock caves will be easily recognizable but not so obvious are the spaces left beneath the spreading boughs of conifers in the northern forests when the snow has already built up around them. A medium-sized tree may have a space right around the trunk or a large one may have pockets in the snow beneath a branch. Try digging under any tree with spreading branches on the Lee side. Even soft snow can be built into a windbreak. Those with equipment can cut blocks. Anchor a ground sheet or poncho along the top with another course of blocks; use others to secure the bottom edge. Use more snow blocks to close the sides.

Snow Construction

A saw, knife, shovel or machete is necessary to cut compacted snow into blocks. The ideal snow will bear a man's weight without much impression being made, but be soft enough to allow a probe to be inserted evenly through it. Cut blocks about 45 X 50cm (18 X 20in) and 10-20cm (4-8in) thick. These will be an easy size to handle, thick enough to provide good insulation, yet allow maximum penetration of the sun's rays. Stack for walls; cover with anything you have.

Snow trench -- Mark out an area the size of a sleeping bag including head support and cut out blocks the whole width of the trench. Dig down to a depth of at least 60cm (2ft). Along the top of the sides of the trench, cut a ledge about 15cm (6in) wide and the same deep. Rest the snow bricks on each side of the ledge and lean them in against each other to form a roof. Put equipment below your sleeping bag so that you are not in direct contact with the snow beneath. Block the windward end with another block or piled up snow. At the other end downwind have a removable block as a door or dig an entrance. Fill any gaps with snow. It is most effective when built on a slight slope; the cold air will collect in the entrance leaving warmer air in the sleeping place.

Snow Cave -- Dig into a drift snow to make a comfortable shelter. Make use of the fact that hot air rises and heavier, cold air sinks. Create 3 levels inside: build a fire on the highest, sleep on the center one and keep off the lower level which will trap the cold. Drive a hole through the roof to let out smoke and make another hole to unsure that you have adequate ventilation. Use a block of snow as a door and keep it loose fitting and on the inside, so that it will not freeze up and jam. Smooth the inside surfaces to discourage melt drips and make a channel around the internal perimeter to keep them away from you and your equipment. Dripping comes from the inside heat. Make sure that the inside dome walls are well smoothed use the back of your mittens or mukluks to do this job not your hand. If the inner walls start to glaze with ice and drip, you are overheating. Placing a piece of snow on the source can stop small drips in igloos.

An igloo takes time to construct but centuries of use by the Eskimo demonstrate its efficiency. Build the main shelter first then dig out an entrance or build an entry tunnel which is big enough to crawl along. You could bend the tunnel or build a windbreak. Mark out a circle on the ground about 4m (13 1/2ft) in diameter and tramp it down to consolidate the floor as you proceed with the rest of the building. Stack one layer of blocks on another and, as when laying bricks, center new blocks over the previous vertical joint. Build up more layers but place each only halfway over the lower tier, so that the igloo tapers in or becomes dome shaped. Shape out the entrance arch as you proceed. Seal the top with a flat block. Make ventilation holes near the top and near the bottom but not on the side of the prevailing wind or so low that snow rapidly builds up and blocks it. Fill any other gaps with snow. Smooth off all the inside to remove any drip-points. This will allow any condensation to run down the wall instead of dripping off.

Igloo - Spiral Method

Lay the first course of blocks and then shape them to the required spiral. You do not have to overhang the blocks if you angle your initial spiral downwards and inwards. Shape the top and bottom faces of subsequent courses to lean inwards. The last few blocks in the center may need some support as you fit them into position. Cutting the first course to an even spiral eases the whole process. Angle the top edge slightly down towards the center. The final block must be cut to fit- unless the space is small enough to leave for ventilation, but this block helps to keep the structure from collapsing.

INSIDE THE IGLOO:

Build a sleeping level higher than the floor or dig down when building to create a lower cold level that can be used for storage. Cut an entrance way through the lower course of blocks or dig a tunnel beneath them. The central hole can be used as an entrance if you are too exhausted to complete the structure.

Parachute Snow house

This is a useful structure if stranded on sea ice where sufficient snow for an igloo for a larger party may be hard to find. Look for snow or convenient blocks of ice in the pushed up pressure ridge of the ice. Mark out a circle and build up a circular wall of snow blocks about 1m (4ft). Leave an entrance space if on ice. You will not be able to dig an entrance tunnel. Dig a lower area in the floor for cold air to sink into. Raise a central column of blocks in the center about 1-1.5m (3-5ft) higher than the wall. Drape the parachute over this and the wall securing it with a further row of blocks on top of the wall. The structure of this parachute roof makes it a snow trap, which could become a dangerous weight poised above your head. Clear accumulated snow regularly. If you want a small fire inside ensure there is adequate ventilation. Site the fire on the outer shelf where it will not affect the canopy, not near the central column. Anchor parachute cords with a block of ice or snow or cut a hole in the ice and pass the top through it to make a firm anchorage.

Living in a snow house

In bad weather MAKE SURE that you have a good supply of timber or liquid fuel, inside the shelter. Do not carry loose snow into the shelter; knock it off your boots and clothing before you enter. That snow would melt inside and make a mess and more dampness. Mark the entrance clearly so that it is easily found. Keep shovels and tools Inside the shelter, you may have to dig yourself out.

Another Igloo - Mold Method

According to the latest researches of the Arctic Aeromedical Laboratory in Alaska, they can not only be built from solid block of polar snow pressed together, but also from fresh fallen snow-as is the practice of the Nunamiut Eskimos in Alaska. When the Eskimos of this tribe want to pitch camp, they pile up branches and bushes and cover them with skins or tarpaulins. Then heap the loose snow on top (use snowshoes as a shovel). After about an hour it hardens and the leaves and branches can be taken away. The igloo is ready.

Koolik for cooking

Pots can be suspended from pegs driven firmly into the walls above the fat lamp koolik or the primus stove koolik. The Koolik has provided heat for comfort and cooking "even cookin-king" for thousands of years, giving a quiet pleasant light and warmth to the native home. Properly tended it does not smoke or smell and it can be controlled to give more or less heat on demand. It is carved from soapstone in the form of a shallow pen of 1/2 moon shape. The straight edge of the lamp is veiled to support the wick made of Arctic cotton or moss. Seal oil or caribou fat is used as fuel. To avoid its melting into the snow shell and to keep it warm enough to render fat, it is supported on short sticks driven into the shelf.

IMPROVISED KOOLIK: (Invented by "AL" KOOLIK?)

You can improvise a fat lamp out of any flat pan, such as a ration can. If you have fat to burn, all that is required is a piece of heavy cotton, linen cloth or absorbent cotton for a wick and a slopping ramp to support it. You can burn lubricating oil in a fat lamp but the flame will smoke more readily and the wick will have to be trimmed more carefully to keep the flame below the smoking point. When the level of the oil drops, the flame may follow down the wick causing further smoking.

A simple damper made of sheet metal will prevent this and will permit closer control of the flame. A few drops of aircraft fuel used with caution will aid in lighting the wick. NEVER try to burn a volatile fuel in the koolik, you would be far too successful and might find yourself in trouble.

Remember that a little animal fat in lubricating oil makes a good improvement in the flame. Body heat is derived from food intake, so eat your entire ration and supplement with fish whenever possible. Eat fat rather than burn them if the supply is low. A diet of meat is good for you. The explorer Stefenson lived for a full year on meat alone to prove this point. You MUST eat flesh, fat, liver and every edible part, to ensure that you don't suffer from dietetic deficiencies.

Remember FAT is ESSENTIAL in Arctic survival don't waist it.

Other Snow Shelters

If you are stranded in forest in the winder and darkness comes simply dig a hole in the snow at the foot of a tree all around it. Cover the bottom of evergreen branches as well as the walls on the outside toward the tree, which you then cover up with snow. It's not central home heating but will prevent freezing to death. Scientists from an Aeromedical laboratory have established that the temperature within such a shelter even without the bodily warmth of those occupying it can be 18F higher than the outside where storms may be raging at 36F below freezing point.

If there are several people in the hole, the temperature will rise even further, this seems the only explanation that in case of avalanche death is due more often to suffocation then exposure.

Shelter Summary

Shelters can be built from damn near anything. Hopefully this section has given you a few pointers. To belabor the point by describing 100 shelters is not necessary. Shelters have walls and a roof. They should not leak, water or wind. They must have ventilation. I watched a made- for-TV movie about a team of athletes that crashed in the Andes. Rather than building warm shelters (They had a multitude of supplies), they remained in a section of wreckage with no insulation. They had cushioned seats all around them and used them all for fire fuel rather than body/shelter insulation. Most of them died of exposure. Instead of melting snow/ice they ate the snow cold. When they thought a plane had spotted them (because they THOUGHT he wagged a wing) they ate all of the food they had left. Remember to drain oil from crankcases before it freezes solid. Fuel will burn slowly if the oxygen supply to the flame is restricted. Exactly how you would do this I'm not sure, just remember to try small first, and leave yourself plenty of room to get out of the way. Burns blister, drawing fluids from the body, remember this before you do something that could result in a burn.

Back to Training