Shelter/Covering

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The purpose of shelter is to create a micro-climate where you can control your core body temperature. The clothing on your back and the material you surround yourself in both offer cover to protect you from the elements, both in a wilderness environment and in an urban one (your home).

In this issue we will be looking at heat loss/gain mechanisms, clothing, man made and natural shelters.

The Rule of 3’s

The military and many other organisations use the rule of 3’s (which could be a rule of 2’s) to highlight the order of what to prioritise in a survival situation (both wilderness and urban), what is important and what is not. The order is not set in stone and depends on the situation, the environment you are in, your condition and your resources.

  • 3 minutes without air (basic life support/first aid) if you are not breathing or bleeding out you’re dead!
  • 3 hours without shelter (clothing, shelter from the elements, core body temperature, fire)
  • 3 days without water (the human body on average can only go without water for 3 days)
  • 3 weeks without food (the human body can go without food for up to 3 weeks depending on the individual and is therefore the last of importance in a short term survival situation)

PLAN

The most common acronym used around the world by both military and civilian agencies to help describe the priorities of survival and the best order in which to do things in is PLAN (Protection, Location, Acquisition, Navigation). It helps to prioritise what is going to harm you first and to address those things first. Like the rule of 3’s, it is adaptable to your condition, environment and your resources.

Protection (first aid, clothing, shelter, fire)

Location (attracting, holding and directing attention, being found)

Acquisition (acquiring water then food)

Navigation (travel, orientating yourself to your surroundings)

 

Heat Loss/Gain Mechanisms

There are five ways that the body loses heat to the environment, they also work in reverse to gain heat.

Conduction

The direct transfer of heat from one object to a colder object. Without an insulating layer such as a foam mat, a person will quickly lose heat to the cold ground or a large rock.

Water conducts heat away from the body 25 times faster than air. Wet clothing will also conduct heat away from the body at a fast rate.

Convection

The continuous movement of air or water over the body stops it from being able to equalise to the same temperature of the body so the body keeps losing heat. Eg. wind chill.

Radiation

Direct heat loss from the body to its surroundings. If the surroundings are colder than the body, the net result is heat loss. We lose 60-70% of our body heat through our head and neck. The naked human body starts losing heat to the environment at 28 degrees celsius. In hot climates we gain heat in the same way from the sun.

Evaporation

Occurs when water (sweat) on the surface of the skin is turned into water vapour. This process requires energy in the form of heat from the body. This is how our body cools itself. One quart of sweat will take approximately 600 calories of heat away from the body. In hot climates, conserve your sweat, not your water.

Respiration

When you breathe in (inhalation), air is warmed by your body and saturated with water vapour. When you breathe out (exhalation), this heat is lost. E.g. in cold air your breath can be seen.

Bushcraft Survival Australia - Heat Loss Mechanisms

Heat loss/gain mechanisms

Clothing

Clothing is your first line of defence against the elements. Your choice of clothing is dependent upon the activity that you are undertaking, what environment you are going into and being prepared for unexpected changes in the weather.

Cold and wet Climates

What your clothing is made from is very important. Wools and synthetics should be your first choice in a cold, wet environment. Wool retains approximately 70% of its insulative value when wet, is moderately fire retardant and smells less making it your first choice, particularly for a base layer. Sheep like it too.

Synthetic/polyester moisture wicking materials are light and dry very quickly so if conditions are wet this is important. Your clothing can also become wet through sweating which is something you need to avoid in cooler environments or if the temperature suddenly drops in a warm one e.g. the desert.

Generally speaking you want to avoid wearing cotton near your skin in cold wet environments as cotton stays wet and is hard to dry, causing you to lose heat through conduction to the damp clothing.

A useful acronym is COLD

Clean – keep your clothing clean. If it becomes dirty it stops breathing and doing its job.

Overheating – avoid overheating. If you sweat in a cold environment you can die if you can’t get your clothing dry. Avoid cottons.

Loose and in Layers – it’s the air trapped between the different layers that keep you warm. If your clothing is too tight those air pockets will be compressed and you will be colder.

Dry – keep your clothing dry.

Layering for colder climates

  • Base layer of wool
  • Warm intermediate layer (wool or synthetic)
  • Optional thicker warm middle layer (wool or synthetic)
  • Waterproof and wind proof outer layer that is breathable.

Remember to include a warm head covering and wool socks.

Hot Climates

In warm to hot climates the focus is keeping yourself cool. Loose fitting cotton material is ideal for this. Take a look at what people in Arab nations wear to keep themselves cool.

During the day in very hot climates you want your clothing to retain moisture (sweat) to keep you cool through evaporation so in this case cotton is good. Synthetic moisture wicking garments are not good in hot climates as they wick the moisture away from you when you need it to keep you cool, making you feel hotter.

However when the temperature drops at night as it does in the desert you don’t want to be wet from sweat so you need to make sure you are dry before that happens and have a warm layer at hand.

Activity

You need to also select your clothing based on the activity you are undertaking. For example, if you are doing strenuous trekking in an alpine environment above the tree line, your choice might be to wear clothing that is synthetic, lightweight, waterproof, wind proof and breathable. However, this same clothing in a woodland or close bushland environment will get ripped and torn so something more durable and tough would be needed.

The Swedish company Fjallraven make a line of clothing that is specifically designed for outdoor use. It is made using Fjallraven’s durable wind and water resistant G-1000 fabric. Their clothing is functional, very durable and comfortable and is designed and manufactured with a number of different outdoor activities in mind.

Some of the garments I use regularly that are great for bushcraft and use in the Australian bush are the Vidda Pro Trousers, Singi Trekking shirt, Vidda Pro jacket, Keb wool shirt and Pine micro fleece top.

Man made shelters

There are many different kinds of man made shelters on the market including various kinds of tents, lightweight tarps, hammock systems, emergency blankets and swags. Some are designed to be used with vehicle camping such as swags (which are too bulky to possibly carry) and some are designed for lightweight hiking. Below are a selection of systems that in my opinion are the best for emergencies, bushcraft and lightweight hiking.

“No matter what kind of man made shelter you choose with the exception of a swag, you will need some form of insulation mat (either blow up up or closed cell foam) to sleep on to prevent heat loss through conduction to the cold ground. 3/4 size is all that is necessary”

Garbage Bag/Drum liner

Large, un-pleated heavy duty garbage bags (hard to find in Australia) are one of the most versatile pieces of kit you can have with you. Uses include: a raincoat (a hole cut in it for your head), a moisture barrier or ground sheet, water carrier, filled with leaves for insulation to stop conduction to the ground, water proofing, a flotation device or cut open and made into a lean-to shelter using a few simple knots and hitches. This can also be combined with a disposable space blanket to make a heat reflective lean-to to keep you warm and dry.

Bushcraft Survival Australia - Survival Shelter

Garbage bag/space blanket lean-to emergency shelter

Re- useable Space Blanket/All weather blanket

These are much more durable than the flimsy disposable space blankets and can be used as a heat reflective blanket, a ground sheet or configured into a couple of different types of shelters as they have built in grommets and eyelets in the corners. The shiny aluminised Mylar side can be turned out to reflect the sun in hot weather or turned in to reflect your body heat or the radiated heat from a fire. They also come in a range of colours so you can also use them as a signalling device to attract attention.

Bushcraft Survival Australia - Emergency Shelter

A student on a course erects an emergency all weather blanket

Hootchie/Light Weight Tarp

A lightweight tarp or hootchie as we call them in the Australian Army is arguably the most versatile light weight shelter there is. Suitable for most climates (not windy), they can be configured into a range of shelter types (A frame, lean-to, pup tent etc) or connected with others (of the same type) to make a larger shelter. A few simple knots and hitches are needed to use them effectively. In wet weather you just set them lower and in clear weather you can raise them.

A light weight tarp shelter allows you to connect with nature in a way that an enclosed tent does not and if you have not tried sleeping under a lightweight tarp than you are really missing out.

To sleep under a lightweight tarp you will also need: a ground sheet, 3/4 insulation mat, sleeping bag and a bivvi bag (water proof sleeping bag cover).

Bushcraft Survival Australia - Australian Army Hootchie

Australian Army hootchie/tarp

Hammock and tarp

Hammocks are designed to get you off the ground which is preferable in hot wet tropical areas where there are lots of creepie crawlies. A built in bug net is also advisable in these areas. Hammocks are also preferable in areas of uneven ground like the side of a hill. You will still need some form of insulation under you such as a half inflated sleeping mat to prevent cold spots and heat loss through convection. In recent years there has been a surge in interest in cold weather hammock camping with a number of elaborate cold weather cocoons and sleeping systems available. Personally I find many of these over complicated and impractical to carry because they are too bulky.

Bushcraft Survival Australia - Hammock and Tarp

Hammock and tarp

Natural Shelters

If you don’t have a manufactured man made shelter with you, you will have to build one using the resources you find around you in nature. There are many different natural shelter types which can all be thatched with an array of different natural materials. Some of these include: lean-to, wickiup, dome huts, various group shelters, debri huts, A-frame shelters, raised jungle shelters etc. Unlike what the reality TV shows portray, building a natural shelter is time consuming and can take anywhere from 3 hours to 3 days to build depending on the thatching material and resources you have at your disposal and the type of shelter you are building.

A few general principles include:

  • correctly siting your shelter
  • sturdy framework to support thatching
  • 45 degree roof angle to achieve water run off
  • thatched in rows from bottom to top with 1/3 overlap to achieve proper watershed without leaks…similar to roof tiles.
  • when thatching with palm fronds, use dead ones as they will not shrink and leave holes
  • an improvised bed to get you off the ground to prevent heat loss through conduction

Bushcraft Survival Australia - Natural Debris Shelter

One man leaf debris hut (NSW)

Bushcraft Survival Australia - Natural Shelter

Lean-to thatched with cabbage tree palm fronds (NSW)

Bushcraft Survival Australia - Natural Shelter with Moss in Scotland

Group shelter thatched with moss (Scotland)

Bushcraft Survival Australia - Natural Shelter

Raised Jungle Shelter thatched with cabbage tree palm fronds (NSW)

Siting your shelter

No matter what kind of shelter you have or need to make whether it be man made or natural, it must be safely and correctly sited. Here are some guidelines:

  • Look up, look down, look all around
  • DO NOT site your shelter under dead fall, a branch that could come crashing down or a sick looking tree. These are known as widow makers for obvious reasons!
  • Do not site your shelter at the very bottom of a hill a valley or a localised low spot if possible. Cold air sinks and those areas will be significantly colder.
  • Do not site your shelter on a game trail or ants nest. You may get a surprise in the middle of the night.
  • Site your shelter on flat even ground so that you get a comfortable nights sleep.
  • Allow for water run off if heavy rain. Where will the water go or pool?
  • Do not site your shelter in dried up creek or river beds. Rain a long way away can cause flash flooding and is very dangerous.
  • In hot climates, try to site your shelter in the shade to allow for extra cooling.
  • Do not site your shelter too close to water as many insects breed in water. Running water will also prevent you from hearing predators or someone looking for you.
  • Site your shelter with any breeze blowing across the front (90 degrees) to blow any smoke away.

ABOUT THE AUTHOR

Gordon Dedman is the founder of Bushcraft Survival Australia (BSA), an outdoor bushcraft survival school dedicated to teaching genuine and authentic modern and traditional outdoor living skills through carefully designed educational courses.

Gordon is a former member of the Australian Army 1st Commando Regiment and is presently a survival instructor in NORFORCE, an Australian Army Reserve Regional Force Surveillance Unit (RFSU). NORFORCE conducts patrols in the remote areas of Northern Australia, working closely with Aboriginal communities.
Gordon is also a Combat Survival SERE instructor (Survival Evasion Resistance Escape) and regularly instructs on RAAF Combat Survival Training School Courses in North Queensland.

Gordon has trained at and completed numerous Survival and Bushcraft courses and certifications worldwide at schools run by Paul Kirtley, Ray Mears, Dave Canterbury, Lofty Wiseman and Bob Cooper.

Gordon also works seasonally as an outdoor guide in the NT, taking
clients on camping expeditions into Kakadu and Arnhemland.

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19 Responses to "Shelter/Covering"
  1. Hellier Mason says:

    Good stuff thanks

  2. Paul says:

    Well written, good pictures. A KISS approach to instruction that I like.
    Very interesting to learn to avoid cotton in cold environent, as I am almost always in a cotton t-shirt.

    • Gordon Dedman says:

      Im glad you enjoyed it. Yes cotton next to the skin in a cold wet environment is not a good idea as it takes a long time to dry. In a hot environment it’s the opposite. Finely woven cotton as an outer layer works well for windy and wet conditions, particularly when it’s waxed as it’s wind proof and also is tough so doesn’t rip easy. Just don’t wear it as a base layer.
      Gordon

  3. Stuart Whitehouse says:

    I read this with the philosophy… “I don’t know everything and I can always learn something.”
    While I didn’t learn anything new on this occasion, but you definitely reminded me of a couple of things I had forgotten.
    Thanks for a good read.

    • Gordon Dedman says:

      I’m glad you found it useful and reminded you of a couple of things. We are all students and never ever stop learning. I continue to take courses with various people around the world, even basic and fundamental courses as everyone does things differently, teaches differently and it’s a different layer of learning. In any martial art, the most important area is the practise and reinforcement of basics which are the building blocks. The same holds true of bushcraft and survival skills.
      Thanks for taking the time to read the article.
      Gordon

    • Gordon Dedman says:

      There is always something new to learn from someone, no matter what their background. You never stop learning and try different ways of doing things
      Thanks for taking the time to read the article.
      Gordon

  4. Craig says:

    Great article. Very informative.
    Cheers!

  5. Justin says:

    I missed this one.
    This is a very good Blog with a lot of information for those that want it.
    Well done and I look forward to the next one.

  6. Kelly Edmonds says:

    Very nice shelter photos. Great blog too!

  7. Tom says:

    Thanks so much Gordon. After your 3 day course in Sydney, coming back to the information and principles here were a helpful and empowering guide to help us selecting clothing, gear and shelter locations appropriate for totally different conditions: hiking the Thorsborne Trail over 4 days in tropical far north Queensland this October. Based on your logical explanation, I had a lot of confidence in our choices and was proved right.

    Also some lessons learned after, such as:
    camping near water = hella lot of biting insects, ouch ouch ouch!
    Use wind strength and direction to influence heating (or cooling in our case) and smoke.

    Every day is a school day, right? we are always learning.

    Best wishes
    Tom

  8. Adriel says:

    G-day Gordon,
    I’ve been looking to purchase a couple of genuine army hootchies. Apart from the hootchies by TAS, they’ve proven hard to find, some say Ebay is the go to. Are there any good places you know to procure the genuine ones, and do you know whether the TAS ones are of comparable quality?

    Cheers,
    Adriel

    • Gordon Dedman says:

      Hi Adriel, yes it is very difficult to find genuine issue ADF army hootchies in surplus stores as one, the army don’t get rid of them and if they are damaged and they do they put a knife through them first (complete waste) and two, there are not many surplus stores around anymore.
      The only way is through eBay or finding a copy that is good quality of which there are a few.
      They are not genuine but we use the “Bush Tracks” brand which aren’t too bad for the price on our courses and they come in Austcam, olive green and multicam.
      I hope that is of help. Thanks for reading and your support.

  9. Shaun Watson says:

    Excellent article and well presented

  10. Brett Harrison says:

    Hi Gordon,
    Well compiled and professional Blog page. I say this with some personal experience. I was previously Chief Instructor and then Commanding Officer of the ADF Combat Survival Training School. I have had the privilege of conducting USAF Water Survival, USN Pensacola, USAF Arctic Survival in Alaska and the full USAF SERE course (Survival.Evasion.Rescue.Escape). I completed the RAF SERE cause as well and was fortunate to have the professional input of international SERE instructors attend my school as students and instructors, professionals from the UK, Malaysia, USA, Sweden and Denmark. Other international military members with a strong interest in this field came and attended the course paying from their own pocket (of course with the blessing of their own national command and that of our own) for the privilege. I would be very appreciative of the opportunity to assist in any way with your endeavours. Please contact me if you are ever interested.

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