FAQ - Equipment - Shelter

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You have been walking all day and now it is time to camp. What sort of shelter do you need? That is going to depend mainly on the country and the weather. A fine night in the Northern Territory is one thing; a howling gale on the Main Range in Kosci or in the Tasmanian Alps is another. What you usually need is a comfortable night, which means shelter from wind and rain and some insulation, although protection from biting insects is also considered essential by most. A wide range of shelters have been used in Australia: herewith some of the more common, skipping houses, old galvo huts, hostels and hotels. Stone huts as shown in the background of the picture below are a bit rare in Australia! I believe that one was probably a couple of hundred years old.

You could start by finding a large hollow log and curling up inside it - which is unlikely for several reasons. First of all, there aren't many hollow logs that large, and even so you couldn't "curl up" inside one. Secondly, such a hollow log is very likely to be already occupied. And you will probably find the inside of a hollow log is quite "organic", and you might get very filthy. Yes, we need a little more than that.

You could also try just dropping a groundsheet down and laying whatever you have for sleeping on top of that, with a bit of insect netting over your face. In fact, this was often done by the drovers in the dry outback, and is still done by 4WD parties in the outback today. You can still buy heavy canvas swags for just this purpose. For much of Australia the weather is a bit variable, and so we would like a slightly more reliable shelter.

Contents

What do you need to deal with?

This should be the obvious question, but answering it is not always that simple. One reason for the difficulty is that people have such different needs, depending on where they are; another reason is that many walkers frequent quite a range of conditions. Getting a single shelter to handle every condition is not that easy - at least, not if you are concerned about cost and weight. So when someone askls 'what tent should I buy', they rarely get a simple answer. So let's start by listing out the different things you might want in a shelter.

You will note I haven't given these any sort of priority ranking. As indicated above, priorities depend so much on external factors.

Rain

I have listed two different sorts of rain above. Don't complain: the English can easily list about 20 different sorts. But there really are some differences. For instance, if a brief period of light rain is all you are concerned about, then something as simple as a tarp might do for a shelter - or even a good bivy bag. But if the rain is going to be more serious then you are going to have to have a little more shelter. We had about 20 mm of rain in 20 minutes at Medlow Gap one night. That's a very flat area, and the soil is very hard. The water was about 10 - 15 mm deep around our tent at the worst. Fortunately we had a 'bathtub' groundsheet: one with very high sides and waterproof up the sides. We were afloat!

The custon in America with tarps is to not have a proper groundsheet. The picture here shows Will Rietveld and Don Johnson sheltering from bad weather for the day under a very light spinnaker fabric tarp. I can only assume that the soil was porous enough that the rain went straight into the ground, rather than flowing across the surface as would happen so often in the Australian bush. Even so, they are fully dressed in their wet weather gear. Hard men.

Another factor to do with rain is the quality of the 'roof' material, whatever the shelter design. Barring rust holes, galvanised steel roofing is pretty waterproof - but rather heavy. Good PU-proofed nylon is not cheap but can be very waterproof, although having the fabric side outwards means you usually end up with a rather wet tent. Older-style silnylon is also very waterproof and does not absorb water, although some of the more recent versions seem to have a much lower water pressure rating and, I am told, can leak under high pressure. It is medium-priced. Cheaper versions of 'coated nylon' usually mean an acrylic coating, and this stuff is not very good at mild pressures. It gets used on cheaper tents - of which there are many, but it can leak very badly after some use. EPIC fabric has been used on some tents and does make quite a good tent for cold snow conditions, but under heavy rain it tends to wet through and then leaks badly. Fancy spinnaker fabrics can be very light, quite expensive, and have wildly different water pressure ratings - going from moderately good to poor. The extremely light and exotic Cuban Fiber fabric is very strong, utterly waterproof, but horrendously expensive and very hard to handle. This is not meant to be an exhaustive listing of tent fabrics; rather it is meant to illustrate the range of possibilities. Unfortunately, what you often get in the catalogues are the vendors' special marketing names, designed mainly to confuse, bewilder, or mislead. It can be difficult to find out what they mean.

Snow

If you want to camp in the snow your shelter has to have some special features. One is simply greater strength: to withstand the weight of the snow on the roof. Snow on a tarp can leave not a lot of space under it, at at the sides, as the pictures in the Tarp section show. Small tents with a single long pole usually collapse quite easily under a snow loading. A strong double-skin 4-season tunnel tent is much better, and if it is cold enough you could consider a spacious igloo, although building one takes a lot of time. However, if the amount of snow-fall overnight is not expected to be significant you can often get away with a 3-season single-skin tent. The big question is what constitutes a 'significant' amount of snow-fall? If your tent survives the night, then it was not a 'significant' amount. Hammocks - can vary. If the hammock stays up, the snow may fall off it, but using a hammock in the snow can be very cold.

But there is a lot more to shelter in the snow than just the roof. The next section is about wind: a very significant factor in the snow. Snow (and dust) can come horizontally, and get under the roof of your shelter. This can be a problem, as this picture from Backpacking Light shows.

Wind, or ventilation

You can have hot and cold winds of course. A strong wind can itself be quite tiring, and getting out of the wind can be an important factor in survival and comfort. It can also mean your gear stays with you, rather than heading over the hill. Tarps are not so good in this regard, unless you can find a really good bit of shelter. Diving into some thick scrub or forest can make all the diference - if there is any. Bivy bags and good tents can be battened down to shed the wind and keep you and your gear safe, and obviously snow caves and igloos are well sheltered. Hammocks - dunno, but could be entertaining!

Keeping flying snow (or dust) out can be quite important. I woke up one night in the snow with a light dusting of fine snow sprinkling over my sleeping bag (and my face). Oops: time to shut down the windward end of the inner tent (a double skin tent, obviously). So I did this, and removed the little bit of snow which had got in. But that was not enough: the snow still came inside the outer tent and settled on the roof of the inner tent. It wasn't all that cold though, so this snow started to melt, and drip through the inner tent onto my sleeping bag and face again. The DWR on the fabric was good, but not that good! The same thing can be said in some places about the rain: it seems to go horizontally rather than vertically. You need to keep it out of your shelter too. Sometimes you need to be able to really seal up the whole windward end of whatever shelter you are using, to keep out the wind and whatever it is carrying. Sealing your shelter up this way can also make the inside of it a few degrees warmer too.But that does not mean you should always seal up the windward end. Doing so can lead to lots of condensation (we'll come to that shortly), while having a bit of a draft going through can help keep things dry. One morning we had a bit of wind all night, but not enough to make me shut the tent up. The morning before we had found a huge amount of hoar frost on the inside of the tent from overnight condensation, and I had to carry that extra weight all day. This morning we woke up to find the wind had dried the inside of the tent out. It wasn't only the tent which had dried out: clothing we had left lying around and our sleeping bags had also dried out overnight. It was a lovely morning.

In fact, this matter of ventilation can be extremely important if you are out for a number of days in bad weather. Sealing up whatever shelter you are using may keep out the rain and raise the temperature a few degrees, but it will also raise the humidity to saturation. Apart from the hazards of condensation falling on your sleeping bag overnight, this also means that your wet gear will stay wet - or get wetter. If you can strike that tricky balance between getting your shelter a few degrees warmer while maintaining some air circulation, gear has at least some chance of drying (even if only slightly) over night.

Insects

Some people just don't know about insects. That may be because some places just don't have insects. All those tarp users in America must have more benign conditions for their camping than a good mosquito-ridden Australian evening. There have been times when we have sat in our fully insect-sealed tent in the evening and not been game to go outside. The noise of all the mosquitoes buzzing around the tent ... Mind you, the Kiwis and the Scots have midges or sand flies to deal with. These are little wee things - they would crawl through some of the larger-sized holes in some insect netting, and they bite like a herd of impoverished lawyers. Well, they can drive you completely mad in a very short time, anyhow. The upshot of all this is that you may, depending on where you are camping, need some good insect proofing. This could be a fully netting-sealed tent; it could be a bivy bag with a light insect mesh thrown over the hood.

Condensation

This is a more technical requirement, and one where many people do get a bit confused. Condensation happens when humid air meets something cold enough to take the humidity level over 100%. You can get condensation inside a plastic bag on a warm day if you try. But it is more likely that you will be concerned about condensation on the underside of whatever 'roof' you are using. It doesn't matter of course that there is condensation under the roof; what matters is when that free water falls off the roof and onto you and your gear. The difference is important.

The picture here, from an article by Will Rietveld in Backpacking Light, shows condensation on the underside of a tarp. Some people think tarps don't get condensation as they are so open to the environment. Well, it happens! It also happens to hammocks and bivy bags, which is why there is so much debate about what fabric to use for the top surface of a bivy bag. Should it be a waterproof/breathable PU-coated nylon (while rain-proof, it will get a lot of condensation for sure), a treated fabric like EPIC (which may leak under heavy rain and can still get condensation), or something like an unproofed fabric with just a good DWR? The truth is, none of them will work every time.

Let us consider tetnts a little more closely, since tents (with good insect netting!) are used so much in Australia. You can get condensation inside a tent quite easily: pick a cold night, close the tent up, and start cooking. That may be a bit extreem, but just your normal breathing is putting some moisture into the air inside your tent, and if it is cold enough that can condense out. However, as mentioned above, if you have a little air flow through the tent you may be able to keep the humidity below 100%. This may suffice to prevent condensation, even on quite cold nights. Me, I love a lttle breeze for just this reason.

But there are some conditions where you can't prevent the condensation. What to do then? Well, that's where a double skinned tent can be so valuable. We use such tents in the snow to keep the flying snow particles out, for sure, but they have more than just that use. Let's close up the inside tent to keep the wind and snow out. I'm assuming the insde tent is a DWR-treated uncoated fabric by the way. Now you should have slightly warmer air inside the tent - just from your body heat. Moisture will pass through the uncoated fabric to hit the colder fly fabroc, and it may condense there. OK, but what happens when it collects and drips? Hopefully the DWR on the fabric of the inner tent will handle this, and let the drops of water bead up and roll off. Yes: you can have some condensation going on under the fly, but the inner tent may be protecting you.

There is another condensation factor which gets some campers very confused at times. I have heard of many reports that a certain tent will let spray come through under very heavy rain. But often I know what fabric they are talking about, and I know that that fabric does not leak like that. What is going on? Well, they are getting condensation on the underside of the tent fly, and when a heavy drop of rain hits the fly hard it dislodges a small drop of that condensation as fine spray. It feels as though the rain is punching through the fabric, but it isn't. Unless the fabric happens to be EPIC, as usued in a couple of American tents. That fabric is not meant for use in heavy rain: it will wet through and you can get a fine spray coming through after an hour or two. But it works great in snow, when it can breathe out your moisture. Well, that is, unless the moisture freezes and turns to haor frost on the inside of the tent, which is normal.

The bottom line here is that you want a genuinely waterproof 'roof' on your shelter, whatever it is, but you can get condensation under many conditions.

Privacy and comfort

This may not seem significant - unless you happen to be female, or your are camping in a popular place with many others. It has also been noted that couples usually prefer more privacy than single males, so a two-man tent has advantages over other forms of shelter for many people.

 

Tarps

Going up in style just slightly from the hollow log we have the basic fly sheet strung over some sticks. This provides some shelter from dew falling, and can be very roomy. We once saw a very large fly sheet pitched near Blue Gum Forest with about ten kids in sleeping bags under it: extremely cheap, but a rather tangled confusion. It reminded us of a clump of caterpillars. The weather was fine; if there had been a storm I think most of them would have got wet.

One of the aus.bushwalking readers contributed an extensive design guide to tarps: everything you could possibly do with a simple square or rectangle of material. I believe you can find ithe latest version in html and pdf formats at 'Equipped to Survive'. Are such tarps suitable for Australian conditions? Well, I am sure there are regions of Australia where they might suit, but even so do remember that most of them don't have any insect proofing, unless you add that to the basic tarp yourself, and they don't have a groundsheet.

In America more sophisticated tarp-tents are a current craze: see for example Henry Shire's web site and look up the 'Tarptent Project' for a full DIY design. This one is illustrated above. Tarps can vary somewhere between an actual 'tarp' and a tent, and three different sorts are illustrated to the left. It seems (to the author) that this craze has been brought about by regions (in America) where there is no rain for six months of the year, and few insects. Add to this the cheapness of a square of fabric, and the availability of ultra-light silnylon fabric, and the overweight tents of a few years ago. Tarps of all sorts have sprung up, from the basic to those with 'catenary cut', fancy elliptic scallops around the edge, and even a few which really look more like a basic tent than a tarp, complete with a groundsheet and some mossie netting. It seems that they are all held up by two trekking poles - a lot of extra weight which does not seem to get counted, especially compared with carbon fibre tent poles.

Most of the American tarp-tents seem to be incredibably low to the ground, like the one to the right. Actually, I think this one is really a poncho or cape. The lumpy bit on the ridgeline is the hood, tied up. The obvious problems with such low ones are a severe lack of room for living in bad weather, plus a regrettable tendency to sag under heavy rain or snow if they are not really tensioned, to the point where they can be touching your sleeping bag. When that happens, condensation follows. As well, the low height sometimes seems to attract a lot of condensation. Some higher ones, like the Henry Shires one above or the front two in the above left picture, look a bit more like a conventional A-frame tent. However, when you take a tarp tent into the snow country the results can be less than satisfactory, as shown in the picture to the left. The back ends of both tarps have not actually collapsed under the weight of the snow: they just look like that. I am told the tarps are meant to be very low there, but I leave it to you to decide whether they will be very comfortable. By the way: they don't provide groundsheets with many of the basic tarp tents: you just have a bit of plastic on the ground, or rely entirely on your bivy bag. That is of course extra weight.

A more serious problem is often the design of the groundsheet, when one is included. Many of them are expressly made flat. That is, they have no side walls. Comments from one of the makers suggets this is quite deliberate: they are made this way to ensure you pitch them in sheltered places where water won't flow. Well, all I can say is that may work in America, but I am damn sure it won't work in Australia! When it rains here there can be water everywhere, centimetres deep. OK, it works in America - mostly. Sometimes, as on the trip illustrated by these pics, things get a bit tight. You have been warned.
Tarp photos from the BPL Gallery and courtesy Glen Van Peski of Gossamer Gear. I have to admit, three hard men at the leading edge of the UltraLight movement in the USA, and a fantastic trip!

A problem noted with the more basic tarps in the rain is that the water runs down the guy-rope holding the high side up, hits the edge of the tarp, and then gets under the tarp, to drip all over your gear. An American reader Freeman Darrick suggested tying a short bit of string onto the main guy just a little distance away from the tarp edge and letting it dangle. The idea is that any water running down the guy-rope hits the string and runs down it, to drip on the ground outside the tarp. I have heard about this trick from other sources since he mentioned it. You will notice a pair of dark glasses hanging from the guy rope on the low tarp - same thing. Of course, an even bigger problem is when the snow starts to creep under the edge of the tarp. Then you have to use a bivy bag, as these guys were all doing.

Against the above problems, basic tarps are extremely cheap, and can be a good (some might say essential) addition to a bivy bag. You pitch the tarp over the head end of the bivy bag, and it lets you get into the bivy bag in pouring rain and allows you to cook from within your bivy bag too. That is not to say you would be very comfortable, but you would survive. However, if considering this idea, it is worth remembering that the weight of two bivy bags plus tarps is probably more than the weight of a good lightweight 2-man tent.

 

Bivy Bags

A variation on the fly sheet is a bivy bag: a protective sometimes waterproof cover over your sleeping bag, with a small pop-up section for your head. The idea is that it is lighter and takes up less ground space than a tent, and should be cheaper. However, things are not that simple. You sweat during the night (unless you are freezing cold), and that water has to go somewhere. I tried a large plastic bag over my sleeping bag once, and woke up with a sodden sleeping bag. So the bivy bag top surface has to breath. For this reason many bivy bags are made from Gore-Tex, in the hope this will allow the moisture to pass through and away. Others use a fabric with a very good DWR for the upper surface.

Some bivy bags have been tested at BackpackGearTest under winter conditions. The predictable problem was encountered. Imagine that the outside is at -5 C overnight. It's pretty likely that the bivy bag will be resting on your sleeping bag in some places, and this means the surface of your sleeping bag will also be below 0 C. Inside your sleeping bag your skin should be at about 38 C, and you will be ever so gently perspiring moisture. Somewhere in between you and the outside world, or in this case the surface of your sleeping bag, the temperature will be around 0 C. Any moisture around will condense out and freeze at that point. Testers found that they ended up with very wet sleeping bags when used in a bivy in the snow for just one night. Note that this is will happen regardless of whether the bivy bag is made of Gore-Tex or whatever else: the high-tech materials bring absolutely no benefit. This is why early Antarctic explorers ended up with their sleeping bags frozen solid and had to pack them on their sleds without rolling them up. In fact, current thinking is that waterproof/breathable fabvrics like GoreTex are actually worse than a non-waterproof fabric for this in sub-zero conditions as the pores all block up with ice. The air movement you get with plain uncoated fabrics does help a little to get rid of the water.

Why does this condensation and freezing not happen in a tent in the snow? Well, I can assure you that it can and does happen in a tent if it is cold enough! But often we seal up the windward end of the inner tent to block most of the wind, so the air around the outer surface of the sleeping bag mercifully stays just above 0C, and the sleeping bag stays fairly dry. Of course, the fabric of the inner tent sits well below freezing, so the moisture condenses on the inside of the inner tent as hoar frost instead. You find that out in the morning when you sit up and your head brushes against it.

Bivy bags are all well and good in utter emergencies and they will keep the dew off you, but they lack a little in comfort when the rains sets in. Just how you get unpacked and into a bivy bag in pouring rain remains a worry to the author, although a bivy bag with a small tarp erected over the head end has often been used. Cooking in a bivy bag in a storm is something I would like to see - from a distance. I gather you can lean out of the bag and cook under the fly sheet. This has got to be the height of (dis)comfort. Several problems still remain. In a windy storm, the fly is not going to keep the wind and rain out very well unless you have it pegged right down to the ground (when it will touch you sleeping bag) and are in fairly good shelter as well. In sustained bad weather, all you can do is lie in your bivvy bag.

Finally, as mentioned above, two bivy bags and two fly sheets usually weight more than one small two-man tent. Actually one bivy bag and fly sheet can weight almost as much as a small one-man tent. They aren't very popular on the east coast of Australia, although they can be useful in some places.

 

Hammocks

Hammocks may be of value in some places, but the author doesn't know much about them. How you cook in one while fighting off the mosquitoes should be interesting. Sharing one should be even more amusing - to watch. On the other hand, at least two brands are now being sold very successfully to walkers in America, so we may yet see some here. Enthusiasts over there claim that almost all problems have been solved. I gather that you string a tarp over the top of the hammock and peg it out sideways for shelter. They do admit that a hammock can be a little cold on winter as gtting good insulation under your body is difficult. A sleeping bag is no use under you as it get squashed flat.

One problem which may occur for much of our Australian bush is the lack of suitable trees at the right spacings with open space between. Another problem may be mosquitoes. Anyhow, experiences are invited. You can also check out the hammock reviews at BackpackGearTest. In the meantime, a reader (Aris Dennis) contributed the following, for which my thanks.

Don’t Mean a Thing if it Ain’t Got That Swing

I’ve been using camping hammocks for about two years. They provide far greater comfort than I’ve ever had on the ground. However, there are advantages and disadvantages to this type of shelter

First, let’s clear up one of the misconceptions about hammocks; a properly fitted hammock does not force you to sleep either on your back or in a banana shape. By lying on a slight diagonal in a hammock, you find yourself lying almost completely flat. Another misconception is that hammocks rock wildly from side to side. This is not really the case either, as your weight keeps you pretty much stationary. In fact, my girlfriend pushes her hammock to make it rock, as she loves the ‘baby in a cradle’ sensation.

Staying warm in a hammock is harder than staying warm on the ground. While a simple foam mat can insulate your backside in a tent, in a hammock it does not work as well. As the hammock envelops you, it flattens the insulation of your sleeping bag not only under your back (where your sleeping mat is) but also around your shoulders. This can lead to chilled shoulders and arms while sleeping. One remedy for this is to use an extra wide pad, or a segmented pad extender (SPE) to keep the shoulders warm. A disadvantage of using a pad in a hammock is that as it cocoons your underside and does not allow perspiration to easily escape. This can cause condensation on warm nights.

Foam pads do have the tendency to slide on the nylon fabric of the hammock, which is why some people have built double bottomed hammocks. This allows them to stick the pad and any other gear in a pocket under the hammock where it doesn’t move around. This type of hammock can be very cheap and easy to make. My first effort with budget materials cost $6. Plans can be seen at www.imrisk.com/zhammock/zhammock.htm .

Another way of keeping warm is to use a quilt strung underneath a hammock, or a sleeping bag that zips around the entire hammock. These are far more comfortable than using a pad, but are quite expensive to buy. A homemade solution that I have tried is an insulated hammock. These are again quite cheap to make: see www.imrisk.com/hammock/warmhammock.htm .

A large sleeping bag which zips around the entire hammock is Ed Speer’s Peapod. With the 900 loft down on the outside of the hammock, none is compressed by bodyweight, as happens on the ground. Ed recommends filling the peapod with spare gear and even dry leaves when the temperature drops radically. Of course, a sleeping bag cannot be zipped around a hammock that has a permanently attached bugnet. So Jack’ R Better invented a quilt that can be rigged to the bottom of a hammock. It also doubles as an insulated poncho, which can be worn round camp. Another quilt, or an opened sleeping bag can then be used inside the hammock. Underquilts start at as low as 400 grams. These can be found at www.jacksrbetter.com and www.kickassquilts.com .

When rain is expected, a flysheet erected over the hammock and drip lines installed on the hammock lines are all that is needed to keep dry. Drip lines stop water running down the webbing and into your bed. [These drip lines can be crucial in bad weather - RNC]

One common misconception is that hammocks damage trees. Nowadays, camping hammocks use webbing, which wraps around the tree and does not cut into the bark. Problem solved.

Most commercial camping hammocks come with a mossie net, either fixed or detachable, but these too can be very easily sewn or customised for a homemade hammock.

The major hammock brands are Hennessy Hammocks (which are beginning to appear in Oz) and Speer Hammocks. These can be as low as 425 grams including hammock, flysheet and netting. Hammocks weights vary depending on the load they are equipped to bear.

One way to set-up two hammocks is to attach both hammocks to the same tree at the head end The foot ends are then tied to separate trees (three feet apart if possible). This gives both hammocks their own space, while allowing you to blow raspberries at your nearest and dearest next to you. The flysheets can then be set-up high overhead, providing a huge area under which to cook and pack up.

Suitable hammock campsites only need to have two trees about 6 steps apart. The ground doesn’t need to be flat or clear of small rocks and shrubs. If a storm or high wind approaches, going down the protected side of a ridge about ten or so meters provides a campsite out of the wind. As always when camping, check the trees above your campsite for dead branches. Once you’ve learnt what suitable hammock hanging sites look like, you’ll realise that a hammock can be hung almost anywhere with trees. No flat or clear ground required! The downside is driving past a park and thinking “hey, I could hang my hammock between those two trees….or those parked cars… or ...”

 

Swags

These are the archetypal bushman bed. You unroll this great big heavy round bundle onto the ground and find you have a groundsheet, a mattress and a blanket, all together. They get used a fair bit by the outback 4WD mob in the Northern Territory and WA. They are far too heavy for a pack.

 

Cave camping

In some parts of NSW it is possible to find enough overhangs in the sandstone cliffs that you can leave the tent behind. These places are known as "camping caves". If you are going to use them, take a large groundsheet: the floors are often dirty with charcoal and dusty too. It's even worse in the rain, when the dust sticks to anything wet. Since camping caves do get a lot of high intensity use, some of them have been mistreated and may now be closed for camping. Keep any cave you use very tidy, make your toilet a long way away, and don't spread charcoal.

What are the ethics of rearranging the floor of a cave to make a level site for sleeping? I don't know. You are making an impact on the environment, which is hardly MIB. On the other hand, if the aborigines had done it 100 years ago it would now be a cultural artefact. Some caves may have archeological significance, and camping in those may not meet with approval from the authorities. Personally, I think a neatly and fairly minimally designed sleeping platform is not very intrusive, but others may disagree.

On that theme, I would personally prefer to see a neat level tidy place for sleeping than the far more common large fireplace with charcoal spread all over the floor. The charcoal you see in many caves has made the floor into a pigsty: too many fires, all too large, and ash everywhere. In a place such as a cave, where there is little chance for the rain to clean away ash, MIB suggests you should be using a stove.

 

Snow Caves and Igloos

This is a specialised subject for ski tourers and is covered further under Ski Touring. A snow cave is dug out from a large snow bank. It may last one or two nights, but after that the roof starts to fall down - at least in our Australian conditions. It takes a huge effort to dig an adequate snow cave: several people and several hours, and needs some experience. The great dangers are a roof collapse and, we are told, a build-up of carbon monoxide and carbon dioxide if the ventilation is not good enough. However, see the reference below about this: the danger may be somewhat exaggerated.

Igloos are built from the ground up. You can do it by hand (which is slow) or use a special device advertised on Ed Hueser's web site. The Ice Tool seems to be a much more efficient way of making the snow blocks, and it even helps with the correct curve of the roof. Again, this takes quite a while to do, but the result should stay up for many nights. There is more info on the Igloos page. The risk of carbon monoxide in an igloo seems to be pretty low if the ventilation specified by Ed is used - see an actual experiment for some real measured results. They make the CO explanation of the snowboarder deaths near Thredbo a bit harder to believe.

An interesting feature of snow caves and igloos is the inside temperature. The dorway is down low, and you are inside making heat. The inside of the chamber tends to warm up to around 0C. This means the insides can be quite comfortable (all things being relative) in temperature, but there is going to be a fair bit of condensation around. If the inside walls are steep the water will run down them; if the roof is fairly flat it may drip all night long over you, your sleeping bag and your gear. A bivy bag or small tarp might be very useful here!

 

Bush Shelters

This refers to the idea of cutting down enough bush to make a small shelter for the night. It used to be popular in youth groups and the Boy Scouts, but you will be pilloried if you try it in a National Park these days. You may also be prosecuted. It is utterly against the principles of MIB.

 

Tents, in general

The traditional bushwalking shelter is a tent. The word "tent" used to mean something like a tarp with doors - like the original Paddy A-tent, strung between trees. Good tents today used improved materials, have more fancy shapes and come with sewn-in groundsheets and poles and insect-proofing. This is a good thing.

The improvement in materials was much needed. The old japara tents (cotton, to those youths who have never even seen such a tent) did leak a little. If you brushed against the roof in the rain a drip started to come through. If the rain was very heavy a fine spray sometimes came through. If the tent was wet on the outside when you packed it, it would be wet right through for the next evening - and leaking. Modern synthetics and proofing has made life a little more pleasant. The sewn-in groundsheet with side walls is a further improvement. I can remember one lad sleeping on a rather short groundsheet (a plastic raincoat actually) in heavy rain. The japara tent roof was fine, but after a while the water level rose so high it started to flow through the tent, and over the edge of his groundsheet. A very wet sleeping bag resulted, and not much sleep. (Epic trip, that one, long ago.) I can also remember another more recent night at Medlow Gap (Kanagra Boyd NP) in torrential rain and hail. We were very careful of the groundsheet edges that night: the water was literally over 10 mm deep around the tent and splashing wildly under the hail. But the high groundsheet edge did its job. My wife made some comment about Noah's Ark.

 

Theory: Desirable Tent Features

When it comes to choosing a tent there are the usual rules. The first is definitely the Ygwypf one; the second is that usually you must make a trade-off between cost and weight on one hand and what you want the tent to do on the other. The third rule is that there are some seriously bad tent designs out there, even in the expensive category. The most common cause for this aberration is an attempt to copy a feature from somewhere else which is utterly unsuited to Australian conditions, although in some cases the author thinks lack of experience (or even plain stupidity) may have played a significant part.

If camping in good weather well below the tree line is your aim, then a lighter tent is fine. In 2003 dollars, about $500-700 should get you a good 3-season tent. If you want to go ski-touring in the Alps, be prepared to pay $900-1100 and expect to carry a little more weight. If heavy or weaker materials are OK, the price may be lower. After all, there are the K-Mart $100 specials, but just remember the Ygwypf rule.

Regardless of whether you need all the following features for what you want to do, you should at least consider them before you buy a tent. The order of listing is not particularly significant.

One could go on for a long time about other features, but these will do for a start. If you can think of others which are important, let me know. More technical information about materials and designs will be found in the DIY section.

 

Un-Desirable Tent Features

You can buy imported tents here in Australia, but many of them are not suited to our conditions. The current American fad, a 'tarp tent', basically reverts to an idea we abandoned 100 years ago. It has no insect proofing and has to be pitched very low to the ground to keep the rain out when the wind blows. It may be light, but so what if you get bitten to death and then soaked? In another aberration, the Americans seem to regard the inner tent with the insect proofing as the "tent", and the outer tent as a "fly". They lay out the inner tent on the ground, erect the poles, hang the inner tent from the poles (or thread the poles through sleeves attached to the iner tent), and then throw the fly over the lot. Actually, one often reads about them not even bothering to take the fly on a trip. Their weather is different from ours! In many regions they 'know' they will get no rain for six months of the year, and that is when they go walking. Windows in the ceilings of the American tents are routine - for looking at the stars they say.

The American approach to pitching a tent sounds simple, but think what happens in bad weather. How do you erect the inner tent in the rain without getting the groundsheet full of water? Worse, try it in a storm! It's a fundamentally bad design for Australian weather. Worse still, many of these American designs can be pretty unstable in bad weather. There is little to stop the poles and the inner tent from wobbling all over the place and collapsing when the wind blows hard enough. And there is not much to keep the erected inner tent on the ground in a strong wind - the guy ropes are on the fly. Usually the guy ropes on the fly are not attached to the tent poles at all, so the poles get no support from the guys. The source of this design probably lies with those areas of America where it simply does not rain for 6 months of the year - or in a desire to make pitching a tent simple for dummies. The big worry is that some Australian manufacturers have copied the American designs. Obviously they have never camped in a storm. Avoid them. (Actually, a lot of these are now made in Asia as cheaply as possible to American price-based specifications.)

You can pitch double-skin tents in two parts, but mostly we use what is called "integral pitching": the tent is treated as a single unit and both parts are pitched together. Some people advocate splitting the tent into two loads for two people, but this is an historic idea and really a waste of time and effort. Good tents are not that heavy today: share another part of the load instead.

Following on from here in the 'farcically bad design department' we have those tents which have the door opening over the groundsheet. This fault is often found in small pop-up domes, especially single-skin ones. Just how you get in and out of the tent in pouring rain without filling up the groundsheet with water is never mentioned in the advertising. They may work at 7000 m for a summit assault party, but not in Australian conditions. This rather wide-spread design is truly brain-dead. Avoid them.

 

A-Frame tents

As mentioned above, the original Australian bushwalking tent was the "Paddy A-Frame". But don't blame Paddy for it: the design is as old as the hills, going back hundreds of years. You take a flat bit of cloth and throw it over a horizontal rope. Options include doors at the ends, to keep the wind, rain and dust out, and side walls to lift the roof off the ground and give more inside space.

You can make an A-frame tent extremely cheaply. However, they don't take the wind all that well, although the side walls (if added) helped keep the roof off you in the wind. This sort of tent does not seem to be very popular today, which is strange as they were used to explore places like SW Tassie. The picture was taken from inside my dome tent on High Moor in bad weather in about 1967: the way the roof is bending shows the wind. The white thing sticking out was a patched backside on the trousers of the guy getting into the tent: rough country. It sticks in my memory that heavy rain did come through the cotton cloth as a fine spray that night, to the dismay of the occupants. (We were fine in my nylon dome.) One could indeed argue that there have been some improvements over the years.

However, just to prove that bad ideas never really die, one well-known American gear maker has recently resurrected the 'lean-to' version of the A-frame. As you can imagine, when the wind blows from behind the amount of space inside sort of decreases. If you are silly enough to have the wind coming from the front it blows up and tries to fly. In effect it is a cross between an A-frame and a 'lean-to' tarp. It is probably OK for those places in America where they have fine still weather for 6 months of the year, but it is pretty useless for serious weather. Another example of 'design for cheap Chinese manufacture' rather than caring about function.

 

Pyramid Tents

There are some "pyramid" tents on the market. These normally use a centre pole and a pyramidal fly, which is pegged out at the edges. In fact, this design is also antique, probably thousands of years old. It is used by desert Arabs, Tibetan herders and Red Indians. Teepees actually had lots of poles around the edges rather than a centre pole, which gave them more free space in the middle, but apart from that they are just the same. They have been used very successfully in the Antarctic - in larger sizes and made of heavier material than a bushwalker would have of course. I imagine the straight centre pole would have to be fairly rugged. I have never used one since my very early childhood. (It leaked at the middle.)

There are several problems with this design: the pole up the middle gets in the way unless the tent is large; they usually don't have a sewn-in groundsheet, and the walls flatten down at the edges when the wind blows, leaving precious little space in the middle. The door usually goes up to the pole, meaning that you are going to get rain into the middle of the tent when you open the door. Unless special care is taken, they are only suitable for very mild conditions. There was an English design ("Blacks") which could take bad weather because it had walls, but it seems to have disappeared over the years. It also had optional external poles, and is shown with them in the background in the picture to the right, somewhere in Wales in 1971.

One modern version of the pyramid is the Black Diamond Megamid. Black Diamond boasts that the absence of a sewn-in floor makes the tent more versatile in pitching on uneven ground, and makes food spills etc a non-problem. This may be so, but the other problems remain. They also have a "dual pyramid" version called the Betamid. This is erected with two trekking poles to make a cross between a pyramid and an A-frame tent. It appears very light at 1.04 kg, but that is without poles, any mosquito protection or any floor. Black Diamond go so far as to claim you can use it ski-touring, but they haven't seen our Main Range with the wind coming up the Murray Valley at 100 kph!

 

Modern integral-pole tents

Modern tents come in several shapes: the tunnel and the dome are obvious ones, but there are some other variations. A common feature found in all of these is a flexible pole structure which is used to hold the roof up. This pole structure is integral to the design of the tent and almost always curved: it is not just a couple of sticks. It is different from tents like the old A-frames which relied on tying the ridge cord to a couple of trees or outside sticks. Adding these special poles to the tent means an increase in carried weight of course, but it also means a better design and greater flexibility (well, usually). After all, there are many places where it simply is not convenient to try to find sticks or spare trees. The alpine zone above the tree line is an obvious example, although many caravan parks would also qualify!

 

Domes and 'pop-up' tents

A dome is usually larger (and higher) than a tunnel and has bigger hoops in several directions. Because the hoops in a dome are larger it is usually a bit less stable in bad weather - but it may be more roomy. The manufacturers try to counter this problem by adding more poles - which increases the weight. We had a large (7' or 2.1 m square) dome in SW Tassie in the mid-60s: large enough for four people asleep, or six sitting up having dinner. On a memorable snow trip on Mt Bawbaw it held about 14 people all sitting up one evening for a party. It may have been the first dome tent in Australia: I had designed and made it myself to replace my Paddy A-frame. It is shown in the old photos above. It was great except when camped below a saddle in SW Tassie: then the wind came straight down on top of it and 'popped' the centre down. The poles were Jarvis Walker fibreglass fishing rod blanks and were not damaged by this, but the young lady who slept in the middle of the tent used to object when thumped in the tummy by the roof at 2 am.

Modern commercial domes are often a little smaller than the one I made and have stronger poles. They are great for three-season use, and can come in larger sizes taking three or four people comfortably. By criss-crossing the poles they can be made sufficiently strong even for 4-season snow use, but then they need lots of poles and pegs. These latter are sometimes called 'geodesic' domes. One version I saw had 5 poles, 26 pegs, and weighed 4.6 kg. It would take 3 people, but with very little room for packs or cooking, and needed lots of pegs right around the edge of the roof. Other models are somewhat better, but are not light. If you don't mind the weight, the larger ones can be quite roomy. There are quite a few of these on the market: a lot of 'copycat' has been done. If you want a dome, make sure it has at least one good vestibule for wet gear and cooking. Two vestibules would be better.

There are two problems with the dome design. The first is that it works best with a square floor, but this leads to a very large tent. When the floor is made rectangular, to accomodate just two people, the pole structure is not as strong. You can't make the tent very long: the dome would just about fall over sideways in a light wind. In the extreme case this leads to the European 'pop-up' tent. This is a small narrow dome with a floor space just large enough for two sleeping bags, and a fly over it with a very small vestibule. You attach the two poles to the inner tent (methods vary), and the tent 'pops up'. Then you throw the fly over it. In theory the tent is self-supporting. This is true - on flat land in a dead calm. In a strong wind they can roll away quite well: it has happened, even with gear inside! The stability is not that great anyhow when the poles are not attached to the fly. The concept of the 'pop-up' has some appeal for novices, but they rarely have enough room in them for two people to actually do anything. The author met two men in the Pyrenees in France who were using one - but one of them slept outside in a bivvy bag to make room for the gear inside. Another case of YGWYPF.

The second problem with a dome tent is they often have rather poor airflow through them. This leads to condensation. Various cunning vents have been devised, but none of them impress me very much. maybe one day soemone will come up with a good design.

 

Hoop or single-arch tents

There is a strange category of 'one-hoop' tents. These are neither tunnels nor domes. They come in one and two person models, and for use in sheltered conditions. Many of them do not have very good ventilation, almost by basic design, and so get a lot of condensation. The pole is of course very long and correspondingly quite weak under wind or snow loading, as seen here in a picture from the Backpacking Light web site. It seems the occupants had to be dug out from the outside as they were not able to dig out from inside. In addition, you will find that both the head and foot ends of your sleeping bag are very close to the roof. This can be slightly claustrophobic, and can put your bag against the condensation. You can imagine how wet the sleeping bags in the picture were in the morning! I saw someone using just the fly of one of these models in the Pyrenees in summer: he spent a lot of time drying his sleeping bag despite the fine weather. Basically, this design is simply not a very good idea for anything other than warm dry mild conditions.

 

Tunnels

The tunnel tent is just that: a tunnel held up with several hoops. The ends of the tent are tapered to the ground for extra stream-lining. It is widely reputed to be the most robust design in high wind and bad weather. The tighter curvature on the poles (compared to those in a dome) gives it considerably greater strength in a storm. Some models have only 2 poles (one at each end), and are suited mainly to sheltered 3-season use. The reason is that the long centre section is nowhere near as robust in a storm as a 3-pole version, which puts another pole in the middle. A good 3-pole version will normally take most any weather you can throw at it, especially if pitched end-on into the wind. This assumes that the two end pegs are well placed: everything depends on the end pegs! You can use tunnels side-on, but then you need to make sure the side guys are well placed. A 4-pole tunnel tent (like the author's ultra-lightweight winter tent) is so robust as to be unbelievable.

A disadvantage of tunnel tents is that they tend to be a little longer on the ground than a dome: the vestibules at the ends take space. You could leave the vestibules off, but that seems very silly. However, the ground does not have to be completely flat at the ends, and vestibule space is extremely convenient to have in bad weather, for packs, wet gear, boots and cooking. On the other hand they are narrower than domes, and this can make it easier to find a suitable tent site. This applies especially when you are trying to put the tent on sloping sand or snow.

A tunnel tent tends to be a bit smaller than a dome, as shown in the picture. However, that doesn't mean you are cramped. A good two-man tunnel is just fine for two people, but you don't often see a four-season three-man one: the geometry doesn't work quite as well. The original Macpac Olympus is probably the reference tunnel tent in this half of the world, especially for snow and bad weather, although it is getting a bit old now and is rather heavy. The author has had one for many many years, and has yet to see any weather in Australia which would worry it. Macpac claim it will sleep 2 or 3 people, but you wouldn't get much sleep with 3 in it! The current (2006) version is made in Asia somewhere, and the design has been changed. The rear vestibule has been sacrificed and the inner tent pushed into that space. Whether this is a good thing or not is open to question. The only benefit seems to be the shorter ground length. The Hilleberg tunnel tents do this too, but they then make the remaining vestibule longer, so you can get into the vestibule in bad weather fully dressed. This idea has some merit. There are other variants on the market, including the author's Ultra-lightweight version shown in the DIY section.

There are some 'two-hoop tunnel' tents on both the Australian and international markets which look like over-sized modified bivvy bags. They are long, low and narrow, or have strange pointy shapes at the head end from strange pole configurations. You can separate these out by considering just how much room you will have inside one. If it looks as though you will be confined to mainly lying down, label it a hyped cocoon (or bivy bag) instead. They can be a little cramped in bad weather, and they can collect an awful lot of condensation.

Availability of Tunnels

Two words of caution are in order here when you go looking for good tunnel tents. A lot of the large '3-hoop tunnel tents' turn out to be designed for car-camping. When you look carefully at the dimensions you realise that many of them are very large (standing room!), and very heavy, with few guy ropes. Others have very long sections between the poles. They are not going to provide a good winter snow shelter, but they were not meant to do so. They are 'family' tents. The second caution concerns actually finding good tunnel tents. A Google search will turn up lots of pages of camping advice which mention how a 3-hoop tunnel tent is just the thing for extreme mountain conditions. But try to find a real 3-hoop tunnel tent for sale: the author found almost nothing via Google in 2002. I know of the folowing:

Steve from the UK mentioned that Jack Wolfskin makes tunnel tents, but the tents are not accessible from their website (bungle?) so I do not know much about them yet. Vaude also make tunnel tents (search for tents, then select the 'scandinavian' style), but these are of an old design and rather heavy. Does anyone know of any others?

Many of the commercially available tunnels are of a fairly old design, where the poles are all of the same same size. They work fine, but I think a more tapered design is going to shed the wind a little bit better. Some of the 3-pole ones from Northern Europe are rather long as well: the span between two poles is used for sleeping, while the span between the other two poles is used for gear and cooking. That said, Hilleberg tents get used in some savage places. Some use the wall on one side of the tunnel as the door: big zips run up the poles. This is fine until it pours rain: zips can and do leak, even when they have a baffle over them. I would hate to have this expensive tunnel tent leaking on my gear! So I still say that there are only a few really good tunnels out there. I admit that making a good profiled tunnel takes a lot of effort, and they are not going to be cheap. Maybe that has something to do with it.

Tunnel Poles

Two configurations are possible for the poles. The most common one is for the poles to be a curve right over the tent, like a semi-circle or half an ellipse. This design is very easy to pitch as the almost-straight poles thread very easily into the pole sleeves. It gives good headroom inside too. There are some disadvantages to the single curve style: for a start the poles are subject to a very high curvature stress in the middle and the flat top of the tent does not shed the rain very well. But a flat top can also collect a lot of snow in winter, and the curve there can straighten out and then buckle. Yes, I have experienced this buckling under high winds. In addition, the high curvature of the poles in the middle can lead to work-hardening of the aluminium, leading to a sudden failure in the field. I have also experienced this! You can prevent this by putting a crucial and carefully calculated 'pre-bend' into some pole segments. The physics or metallurgy gets a little complex here, but the author can guarantee the possibility of failure (sigh). The flat top can be dealt with by making the material quite waterproof, but this doesn't get rid of the snow. If it is snowing heavily, you have to sit up in the middle of the night and give the snow on the roof a thump to make it slide off - regularly. This does work (he says also from experience).

The other pole configuration uses one or more gentle bends in the pole around the top, meaning you have to be just that little bit more careful threading the poles in place. This allows the use of straight aluminium poles or carbon fibre poles. The latter are lighter and stiffer than many of the aluminium ones. The right sort of carbon fibre tubing can be quite robust as well. With only one bend the headroom is somewhat limited, although experience shows this is not a really significant problem in practice. With three bends the headroom can be very generous: there is as much headroom as with a fully curved pole. It just means threading the poles into the sleeves takes a little more care. A significant advantage to having bends in the design is that the steeper slope across the top makes the tent shed rain and snow much better.

Tent Pegs and Guy Ropes

This exceedingly worthy subject now has its own page here.

 

Tent Poles

Just as a tent needs pegs to keep it down, it also needs poles to keep it up. Back in the days of Japara A-frame tents one grabbed a couple of sticks lying around and used them. American tarps are often held up with their trekking poles. (An interesting concept: you save a bit of weight by using a tarp tent, but then you add the weight back by carting around two superfluous and very expensive trekking poles. Great marketing.) But today's shaped tents seem to need something just a little better suited than that. The technologies available include:

Easton tubing

Many of the golden tent poles you see are this stuff. It is indubitably very good, having served for so many years. The origin for this as a tent pole is interesting: Easton Archery started life making wooden bows and arrows, and then moved to high-tensile aluminium tubing for their arrows. They actually make their own tubing from sheet and temper it to an unbelieveable T9, and as far as I know are the only firm making tubing to this hardness. The tent poles are just a spin-off from the arrows, their main market. There are actually two allows available from Easton: the original 7075 alloy and a newer 7178 alloy. The latter is slightly stronger but a bit more brittle, and has never really taken off.

Easton poles are basically a simple tube with a ferrule poked up inside one end. This is simple and lends itself to easy repair or modification, but may not be the lightet possible approach.

There are a few problems with Easton and their poles. The first is they think they have a monopoly, and just don't want to talk to you unless you want to buy 10,000 pieces. I have heard them described as arrogant. Certainly, they never replied to any of my email queries. The second problem is that their technology seems to be static, as of maybe 1980. It's good, but not perfect. And thirdly, some people find the T9 hardness a bit unforgiving: the poles can and do snap.

I gather Easton are moving their production plant to Bangladesh. They claim this is to stop the local workers from pirating their technology. Does this imply that they think the people of Bangladesh are that primitive? One wonders whether the cost of labour has anything to do with it.

DAC poles

So what is a small strugging tent maker to do if Easton just ignores him? He looks elsewhere, and this creates an opportunity for another firm. Hence Dongah Aluminum Company of Korea, or DAC. Their first web site seems to have been abandoned, but they have a new one for tent poles called mypole.com. DAC do not use the 7075 alloy; they use an older and slightly softer 7001 alloy. I am not sure how far they temper it, but they too may be going as far as T9. Now this by itself is not enough to displace Easton, so DAC have been innovating. Instead of taking a simple bit of tubing and sticking a ferrule up one end, DAC have developed techniques to form the end of a length of tubing into a ferrule. Further, they woke up to the fact that the damage to a pole is nearly always at the coupling. This means they can make the main section of their poles thinner and lighter, as long as they reinforce the coupling region. This they do by swaging in very thin sleeves at the ends in a feat of considerable engineering elegance. Their web site has some interesting information on aluminium properties and how they make their poles.

They make several different series of poles, with 'Featherlite' being a major brand of theirs, and they are starting to eat into Easton's market. I gather even companies such as Macpac are starting to use Featherlite poles. Certainly, they are very elegant. Whether they respond any better to email queries is something I have not tested.

Other Aluminium poles

There are other manufacturers, but I know little about them. I have seen golden orange poles which look a bit like the conventional Easton ones, but they are weaker and don't have the Easton logo on them. Asian copies I suspect. It is interesting that a lot of the broken ones at my local gear shop were actually of this no-name brand rather than Easton. Maybe the cheaper tents they came with were bought by less experienced campers? And I have also seen plain poles and blue poles, but I know not the sources.

Fiberglass

I first used fibreglass poles in the 60s, when I made a dome tent. I used blanks from the Jarvis Walker fishing rod factory. They worked quite well, but the long spans across the dome meant the poles could go into S-bends in bad weather and let the tent change shape abruptly. But they never broke. Since then hollow fibreglass tubes have become the default cheap pole for the cheap Made-in-Asia tents you find in supermarkets. They work reasonably well, but they are heavy and can develop acute bends when the resin fails. They aren't made as well as the fishing rods, and some of them seem to have plated steel ferrules - which rust.

Carbon Fibre

What is stronger and lighter than 7075 T9 aluminium? Without doubt, carbon fibre (CF). And today you can buy several sorts of carbon fibre tubing at reasonable prices. But before you do, you need to consider what sort of tubing you want for a tent pole.

A lot of CF tubing is being produced for the kite market. You might be amazed, but it seems that kite making and flying is a huge sport, especially in the USA and the UK. They use CF tubing (and Spectra string) in their kites, for strength and lightness. Does this mean that kite tubing would suit a tent? No, unfortunately not. The reason lies in the fine details, but note two key differences between kites and tents: tent poles are curved while kite spars are not (significantly), and the consequences of a broken CF tube are very different for a kite flier and someone camping in the mountains.

Pultrusion

The simplest technology for making either fibreglass or CF tubing is the same; they are the same things really. You pull a whole lot of strands of fibre through a die with some resin forced into the space between the fibres, and this is called the 'Pultrusion' process: a pulled extrusion. It makes a fantastically stiff spar, to be sure. But bend it just a little too far and the tube will split its full length in a flash. The two parts are then very weak. This might not be so clever when you are camped in the snow in a storm. The reason is that the only strength the tube has around the circumference is due to the epoxy reson, and this is not that strong.

Fabric wrap

The next way to make tubing is to take a polished rod and wrap very thin woven CF fabric around it. The fabric is called a 'prepreg': it has the epoxy or polyester resin previously impregnated in it already. Heat and pressure (plus a few other details) and you have a tube - provided you can get the polished rod out of the middle. This fabric has strength both along its length and around the circumference, due to the weave of the fabric. In addition, the weave of the fabric allows some flex inside the structure, so the tube is not as stiff as a pultruded one and is much more forgiving of bends. The problem with this process is that it is fairly labour-intensive. You can get such poles from Fibraplex in America. (2006: it seems that the Fibraplex company may have automated the manufacturing process or found a suitable Asian supplier. I don't think they are hand rolling any more.)

Multi-layer radial wrap

The third way to make a strong tube is to combine the first two ideas. You pultrude some fibres through a die into a very thin-walled tube, then wind more fibers around the tube very tightly, then pultrude more fibres along the length, then wind more around the tube, and so on. You can build a machine to do this on a continuous basis, with quite high tension in the wrap and good qality control. This is called an N-layer radial wrap. It is what I use for my tents. I know of at least one Korean firm doing this, in volume.

Carbon Fibre Tube Strength

Carbon fibre tubing would not be much use if it was fragile. My experience is that the fabric and radial wrap versions are not. I took a couple of bits of pultruded and radial wrap CF tubing and did some tests on them. (I wasn't able to do this with the Fibraplex poles as they had been sold with a tent.)

Crush with pliers
The pultruded tubing collapsed by fracture of the resin. The radial wrap tube did not collapse, but a section delaminated and flaked off.

Stand on tube on rock
Several people have tried this. I took a piece of radial wrap tubing, put it horizontally on sheet rock, and stood on the end of it with soft and hard soles. There were awful grating noises, and some surface scratching, but the tube was not really damaged. I would not try this with pultruded tubing.

Jump on tube on rock
Several people have tried this too. Continuing on from the previous test, I jumped on the end of the tube with soft and hard soles. OK, this was just an extension of the above test. Again, there were awful noises, some surface scratching, and a little bit of cracking and delamination neat the end. But the cracks did not propagate. I would not try this with pultruded tubing.

I mentione that the pultruded tubes can split very abruptly down their entire length. The radial wrap tubes can be split at the ends by too much force being applied to an internal steel ferrule. I had to replace a pole with a split end for one of my customers when they didn't socket the ferrule all the way. However

Bending tent poles

Many of our tents have the poles bent into quite a curve. Now a curve has a lot of strength, but there is a limit to how far you can bend any tube before internal stresses cause a problem. The limit is usually expressed as a percentage strain, which is a measure of the difference in length of the top and bottom surfaces of the tube. The elasticity of the material will allow a certain amount of strain, but beyond that the material looks for ways to fail. Taken too far just once the materail can snap; taken almost too far many times it work-hardens, and then snaps.

The normal way of handling this for aluminium tubing is to give it a 'pre-bend'. The logic may seem strange here, but it works. What you do is put a bit of the bend you want into the tube so the tube stays bent. Then when you bend it to the full amount you want, the extra bend or stress stays below the elastic limit. But why doesn't the stress put in by the pre-bend matter? Well, it seems that with some alloys you can 'stretch' the material once or twice and have it 'relax' and accept the new shape. So you carefully bend the tube under very controlled conditions to a half-way shape, and let it be. You do not keep changing this pre-bend!

This works with aluminium alloys (and stainless steel). It does not work with CF tubing! If you use CF poles you must either stay within the elastic limit, which is a very shallow curve, or add short bends or elbows. The tubing itsdelf will stay straight. Some tents even have these elbows with aluminium poles, where abrupt bends are required.

Joiners

Very rarely can you carry your tent poles in one piece. That means you must carry it in sections, and join those sections together in the field. The joining is done with joiners. These are typically an inside ferrule or outside sleeve. An engineering rule-of-thumb is that the length of such ferrules should be 7 times the diameter. That's fine, but what happens if you don't mate the join properly? In short, disaster. The end splits open and bit break off. This is not usually repairable in the field.

Gear shops do a good business repairing poles where the user has not made the join properly. They sometimes have buckets of broken poles pieces out the back. The ones in the picture here were collected from one shop on one visit: they are not my disasters. If you value your tent, check every join you make in the field - carefully. And when you get home, clean the joints and check them for cracks which might herald a forthcoming failure. Field repairs are possible: see below.

Bungee cord

You will normally find that your segmented tent poles have bungee cord up the middle. There are more reasons for this than just ease of assembly and keeping the right pieces together. That bungee cord also holds the joins together as you thread the pole into the tent. It is very often what prevents your joints from the disater outlined above. Finally, it also helps you get the pole out of the sleeve in the tent - so you don't leave one or two bits still inside. You should make sure this bungee cord stays in good condition.

 

Other Tent Accessories

Pole plates
While rarely used in Australia, some conditions need little "dinner plates" under the tent poles to stop them sinking into the ground. The one place you may need something like this is in soft snow, and this is covered in the ski touring section again.

Guy Rope Toggles
The standard method of adjusting a tent guy rope is with a guy rope hitch. This is like a clove hitch, but because it has an extra turn it tends to bend the main rope and this adds to the friction. These work very well on most nylon ropes. However, you also see small guy rope 'toggles' on some tents. On family marquees these are often made of timber (which grips well), and I have seem aluminium ones on some bushwalking tents. In general they are not needed - until you change to one of the more modern strings made from Kevlar, Spectra or Dyneema for instance. These materials are so hard they do not deform much inside a guy rope hitch, and the hitch does not grip. So if you are going to use a very thin guy rope of these materials you may need to use little toggles. At present you can't buy them in the shops, which is unfortunate. But see the DIY section and the My Designs section for designs you can make yourself.
Alternately, tie a fixed loop at the end of the Spectra string and move the tent peg to adjust. This works, but is not as convenient for small adjustments.

 

Tent Sites - safe or otherwise

OK, now you have your tent, where and how do you pitch it? In fact, this is not such a silly question. "In the good old days" one found an open paddock, pitched the tent, and dug a storm drain around the tent. Since we go in for MIB these days, don't usually carry a trenching tool with us, and try to not camp in the middle of paddocks anyhow, we need to be a little more cunning.

Obviously you need a level tent site of adequate size. If it slopes just a little, put your head uphill and be satisfied. But avoid a site which has a high point in the middle: go for a slight hollow instead. That hollow will be where your hip goes. And avoid a tilt to the side if possible, otherwise you will spend the night rolling sideways - or being rolled on.

When you pick a tent site, ask yourself what it will look like in pouring rain. If that nice little hollow is right in the middle of a small creek-bed, it could be embarrassing. We have seen a couple forced to pick up their tent at dusk, in the rain and with all their gear still inside, and march it out of a depression which had filled up. A long, long time ago the author camped (just once) in a flat plowed field: rain did not do it any good at all.

Then look at the prevailing wind, and try to put the tent with the back end into the wind. Most tents work best that way, and you don't get the wind driving in the door. Of course, if the wind is blowing uphill, you have a conflict here. In that case, try to camp on the other side of the hill, or get some sort of windbreak upwind. If there is a vestibule at the windward end, put the packs in there as a windbreak.

The next thing to look out for are trees overhead. European pine trees might be safe, but Australian gum trees have a bad habit of dropping dead branches even in still air. We have some tall Sydney Blue Gums at home, and we have often retrieved a 2 metre long 30 mm diameter straight branch from under one of them, where it had speared 30 mm straight into the ground. Your tent roof will not deflect that! Dead wattle trees get borers inside them, and huge sections fall off at random. Worse still was the whole tree which fell over in bad weather near Dead Horse Gap (KNP) and crushed a tent (and sleeper) under it. So, watch out (look upwards) for trees.

Just to make things more difficult, you also need to look at the ground for rocks and sticks. We have seen some sites which looked flat, but had sharp rocks embedded in the ground. Not at all comfortable, and a bit damaging to the groundsheet. Further north or inland you can get sharp grasses which will go straight through your groundsheet (and your air mat too!). You really need to go over the site rather carefully with your hands if you want a comfortable night and an undamaged tent. If there are too many small pebbles there, put your camping nat inside immediately and only sit or kneel on that. The distributed pressure does help a bit.

Some places need a little "engineering" to be useful. This is where you have to use a little judgement with regard to MIB. A sandy river bank or some open ground in a dry sclerophyl forest can be safely redesigned, but an alpine herbfield should be treated with more respect. We have even managed to camp on the extremely lumpy rock layer covering a glacier in Nepal, but that took a lot of careful rock packing! And it was someone else's tent and someone else's ice axe that were used.

Sloping sandy river banks can be converted into good tent sites quite easily, and will be rearranged in the next flood anyhow. A little "cut and fill" with the sand can be quite productive, but you will need to reinforce the lower edge to stop the dry sand flowing down hill. We have put a few dead logs across the slope and shovelled sand onto them with great success -just like making a site on a snow slope. It helps to hold the logs in place with some stakes or some rocks of course, and these can be removed the next morning to reduce the visibility of the site. If you have ever seen some of our rivers in flood you would realise that any rearrangements you might make to a river bank will be very transient.

If you are camping in the alps it may be a good idea to avoid that beautiful flat grassy site right by the creek. If it is a clear night you may find out why so many lovely grassy valleys are termed "frost hollows". We hit -17 C one night by the creek near Grey Mare Hut in KNP. Beautiful site, but our ski boots were blocks of ice in the morning! If you move up into the snow gums you will be lot warmer - and they deflect the wind too. Snow gums don't drop too many branches in my experience, but don't do that in the tall subalpine timber: falling branches do happen there.

Sometimes, you just don't have much choice about where you camp - as in the picture to the right. It's a hard life...

 

Tent Maintenance

Something forgotten by some people when they use a tent is that the tent may get wet. Well, obviously! But if you take the tent home and just put it away, still damp, it is going to grow mould eventually, and this will damage it. And the tent will pong badly when you go to use it again. Always hang your tent out to dry as soon as you get home - not the next week.

There have been regular cries for help on aus.bushwalking from people have have not dried their tent and want to know how to get rid of the mold. Well, it is a mold, which is organic, so you can try a bleach: either harsh chlorine or enzymatic. The general experience is that neither is ever totally successful, and the tent cloth will be damaged by the chlorine bleach as well. If you know of a guaranteed solution, please let me know, but otherwise we have to congratulate you on a learning experience.

When you hang your tent out to dry after a trip, check it for damage. It is far better to repair a small bit of damage now than to have a major problem later. Coghlans sell a pack of adhesive nylon cloth pieces which are excellent for small permanent repairs, on dry cloth. Check the fly and groundsheet fabric for any little holes, or places on the groundsheet where the waterproofing has failed - and patch them straight away! Check the guys for fraying, and also check the poles - carefully. The high-tensile aluminium poles can develop cracks at the ends if they are not correctly and carefully assembled each time. These cracks are very fine and run parallel to the tube. Then the pole breaks in a storm, and you have a real problem! Also check that the joints are clean, so the poles go together easily. A tip about those poles: when assembling them, do not let them snap together. The shock can lead to splitting over time.

Some regular TLC helps. Every now and then wash your tent, rinse it carefully, and then treat it with a good Durable Water Repellent. This helps keep the tent waterproof, which was the original idea. The DWR won't last forever, so when your tent gets wet under light rain, rather than having the water roll off it, do it again. Doing this keeps the tent lighter too, by stopping the fabric from absorbing a whole lot of water for you to carry. Alternately, get one made from the new silnylon: that material does not absorb any water at all. Check and clean all pole junctions as well. I don't recommend greasing the couplings as dirt sticks to the grease, but a dusting of graphite powder wouldn't hurt.

 

Drying tents

Drying your tent out after a trip is more than just a way of preventing the growth of mold however. The polyurethane proofing layer on most common tent fabrics will actually absorb water over time, and then it goes sticky, gooey, and disintegrates, When this happens the fabric is ruined. Forget it: you can't restore it.

The light silnylon fabrics are far more resistant to this sort of degradation, but maybe not entirely if you add lots of UV from the sun. An American maker of UL gear claims that you can use silicone sprays to help rejuvenate the surface of silnylon fabric. This may be so: I am left to wonder whether the silicone spray can react and bond with the existing silicone polymer. However, I have not seen any evidence of needing to treat the surface of my silnylon tents yet, despite many years of use. I have not included the URL for the American web site as the author of it seems totally confused between silnylon fabric, where the cured silicone polymer is bonded right through the fabric, and silicone DWR liquids. I know that the silicone DWR sprays last very little time in the field.

If you find a pole is starting to crack, face reality and get it replaced at a bushwalking shop - before it fails during a trip. If you are replacing a pole and the original one had a curve in it, you will need to get a similar curve put in the replacement. Good bushwalking shops often have a staff member who knows how to do this, even if the method is a little 'rough'. The pre-bend is essential to limit the flexing in the poles as explained above.

Field repair of poles

Good tents often come with a sleeve section which can be slipped over a broken pole. You may need to clean up the ends before they will go in. Carry this insurance, even if you never use it! If you don't have such a repair tube, take the wall of an aluminium soft drink can (the proverbial 'Coke' can) tightly rolled up into a similar sleeve in your repair kit, with some fine string. The picture to the right shows a real repair, using a French aluminium sardines-in-tomato-sauce 'tin' I found on site, but never mind. You will see that I covered the ends of the repair with some adhesive nylon cloth to avoid having it tear the pole sleeve in the tent. The repair lasted for several weeks (fortunately).

The fibreglass poles you get on cheaper tents will take a fair bit of abuse, but they too can fail. They can split or buckle: both are usually fairly obvious. You can get replacement pole kits at bushwalking shops or at places like K-Mart, if you bought the tent there. The tubing trick may work on these too.

Right now you are not too likely to meet carbon fibre poles, but they are available in America (and the author is using them on his tents, as shown in the DIY section). The pultruded ones can also split their entire length if bent too far or if you don't join them properly. This cannot be repaired at all, making this design a bit risky for a tent pole. The wrapped-cloth ones are a bit more robust and slightly less stiff. The multi-layer radial wrap ones can be surprisingly strong. In fact, most poles do have to bend, so too much stiffness is not a good thing. When the latter two sorts fail they usually make a complete clean fracture. Repairs to them could probably be done in the field with some Coke can material, although I haven't tried it. Carbon fibre poles are extremely light, but may not be suitable for your first tent. You can buy replacement sets from Fibraplex in the USA for some tents (see the DIY section).

 

Cooking in a Tent

Vendors of tents and stoves warn against cooking even in the vestibule for fear of carbon monoxide poisoning. They repeat this in a sort of rote legalistic chant, mainly (imho) because the other guys also repeat it. However, the chances of this happening when a storm is raging and the tent walls are flapping madly seem pretty remote. The author has cooked in his tent for years: all that happened was that the steam and other gases quietly drifted out the vent at the top, and we enjoyed dinner nice and dry. Legal caveat: this is not advice, just the author's experience. See Stoves for more discussion of this, and here for some measured results on actual levels of CO in a sealed igloo.

Far more serious is the risk of flames from the stove setting the tent alight, especially when priming a liquid fuel stove. There have been accidents this way. And of course, if anything does go wrong you may have to act very quickly to save your tent. Be really careful over this, and try to light any liquid fuel stove just outside the tent before bringing it in - or use a gas stove.

 

© Roger Caffin 1/May/2002