If you are going on an adventure, taking part in a multi-day race or basically going on a one night jolly in the wilds somewhere, a sleeping bag is going to be an essential item.
Choosing a sleeping bag one would think is easy… Go to a shop, find one that fits into your budget, purchase and use.
The reality is, the above is far from the truth.
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ASK INITIAL QUESTIONS
A good sleeping bag is not cheap and going cheap is most certainly not a good idea. So, from the off, accept that you will need to dedicate a good portion of your hard earned cash.
One sleeping bag will not work in all situations, however, if one is clever, one can make a sleeping bag adapt to other situations and therefore it is possible to increase the range of use and temperatures that a sleeping bag will work in.
Sleeping bags mainly use two fillings: Down or synthetic such as Primaloft.
- Down: Is lighter and the weight to warmth ratio is higher. It packs smaller and can be compressed to a very tiny package if required. Down however cannot get wet. If it gets wet it all sticks together and will offer no warmth at all. Down is expensive and one should make sure that if purchasing down that it is ethically sourced.
- Primaloft: A synthetic product, it is heavier and packs larger than down. It’s a cheaper product than down and importantly it can get wet and still retains warmth.
The first questions one should ask are:
- Am I using the sleeping bag in a dry or wet climate?
- Is the weight of the bag really important. Normally the answer here is, if you are carrying it, yes, the weight is important.
- Do I need the sleeping bag to pack as small as possible?
- Do I need the bag to work in one or more situations? Another way of looking at this is, do I need to compromise on points 1-3 to get value for money.
Ask some personal questions:
- Do I sleep warm?
- Do I like to be warm and if not warm, am I miserable?
- Am I prepared to be a little cold to be as light as possible?
- Do I need a full-length zip, half-zip or am I happy to have no zip?
Consider other factors:
- If you are tall, wide, have big shoulders etcetera, etcetera then some sleeping bags will just not work for you as they will be too small.
- If you are small/ petite an off-the-shelf sleeping bag actually could be too big for you, this is not a huge problem, but if you wanted the bag to be as small and light as possible, you could go custom made.
Sleeping bags have a ‘Comfort Rating’ as follows:
Upper limit – the highest temperature the average male can expect to have a comfortable night’s sleep at without too much sweating.
*Comfort – the temperature at which the average adult woman can expect to have a comfortable sleep. *This is the ideal for most people choosing
Lower limit – the temperature at which the average adult male can expect to have a good night’s sleep in a curled position.
Extreme – the lowest temperature at which the average adult woman can survive. This rating comes with caution and additional consideration should be given if you plan to sleep in temperatures this low.
Layering:
Irrespective of what sleeping bag you choose. Layering for me is a key consideration when choosing a sleeping bag and this is one key factor that helps make a sleeping bag stretch over a multitude of uses and temperatures. (See the image below.)
- Sleeping alone.
- Sleeping bag, T-Shirt and shorts.
- Sleeping bag, L/S top and long leggings.
- Sleeping bag, L/S top, long leggings and Jacket (down or primaloft).
- Sleeping bag, L/S top, long leggings, Jacket (down or primaloft) and over-trousers (down or primaloft).
Note – By wearing a hat/ Buff/ balaclava or combination of all three, you will retain a great deal of body heat – remember this!
With the above diagram, you suddenly see how one sleeping bag can cover at least 5 temperature ranges and still provide comfort.
From a personal perspective, I prefer a sleeping bag that is probably not quite warm enough as stand alone for my chosen environment. Why?
- Should the weather be warm, I know my sleeping bag will be fine on it’s own and if it has a zip, I can regulate even more.
- I know that I can get warm by incorporating layers.
How do I know what layers I will need and what about additional weight?
The answer to the above is actually part of the process and in some ways, part of the fun of what works for you. Let’s take two scenarios, Desert and Himalayas:
Desert:
Multi-day desert races such as Marathon des Sables, require runners to carry all they need for the duration of the event. Therefore, weight is critical. However, desert temperatures can vary greatly. Some evenings can be mild and even hot. Other nights you can be blasted by wind and sand and the temperature drops to zero or below. So, the sleeping system needs to potentially cover a range of temperatures, let’s say 10 degrees. If you purchase a sleeping bag that is warm at say zero, it is going to be way too hot at 10 degrees. The sleeping bag will also be heavier and pack larger. By contrast, if you had a sleeping bag that was good for say 5 degrees, not only will it be lighter, pack smaller but importantly it will be more comfortable in warmer temperatures. You then make the bag warmer, should you need by adding layers… hat, T, shorts, longer leggings and then finally jacket. A question is often raised about the need for a jacket? I personally think it is essential – they are perfect in the morning and evening when sitting around and importantly, they are that extra important layer if you get a cold night. From my drawing sample, you would be looking at 1 to 4.
“Smart lightweight campers have been using their clothes to boost the warmth of their sleeping bags for years and climbers do it when they have to. Yet most of us are still carrying bags much bulkier and heavier than we need.” – Peter Hutchinson Designs
Himalayas:
The principal of the desert applies to the Himalayas. But obviously, one would not use the same sleeping bag. The initial starting point will be a warmer bag that is obviously heavier and larger. Also, down would almost certainly be the choice. The layering would go from 1 to 5. The reason being that daily temperatures in the Himalayas can be say, 10/15 or even 20 degrees. In the evening, depending where you are and how high you are, the temperatures can be -20. That is a huge difference and therefore you need a system that works over a huge range – this can only come from layering! Read about my Three High Passes Trek HERE
NOTE: Both of the above systems benefit greatly from a good sleeping matt that provides a layer between you and the ground. This is an essential item in my opinion. Not only does it add a barrier, it importantly adds comfort. If you are comfortable, you will sleep better. A good nights sleep means you are fresh and recovered for the next day’s challenges.
Professional explorer, Eric Larsen commented to Outside online:
“Larsen firmly believes in layering heavily in the cold, an opinion developed after years spent sleeping in subfreezing temps. “There is no such thing as a cold night’s sleep, only not enough layers,” he says. “I layer when I’m inside the bag just as much as I do while outside the bag. When you’re climbing Everest, you’re not naked under your down suit. The more heat you can preserve in a warm layer next to your body, the better.”
url https://www.outsideonline.com/2271191/how-experts-layer-sleeping-bag
PRODUCTS
Choosing a sleeping bag is something very personal and we are all individual. A 6ft 2” guy weighing 85kg is going to need something very different than a 5ft 6” woman weighing 55kg, so, keep that in mind!
You know you! It’s ok to ask for advice and recommendations, but you need to keep the points above high in your mind.
There is a general rule with sleeping bags and down jackets, the more you spend, the better they are. But there are many options out there.
Understand that when purchasing a sleeping bag that often it is possible to choose a size, just like when purchasing clothing.
A UK based company PHD (Peter Hutchinson Designs) takes things one step further and can custom make a sleeping bag to your exact specifications and needs. “…a footzip, which adds 10g and allows some air circulation around the feet. Zips are an option on the Minim bags, but most competitors don’t ask for one. A short zip with draft tube adds about 55gm (2oz): a full zip and tube adds about 120gm (4oz). Zips also add to the packed size.” One of the advantages of PHD is you can get exactly what you need.
A few years ago I compared PHD, OMM and YETI at the Marathon des Sables HERE
In a recent article, I compared Rab, Sea to Summit and PHD HERE
CONCLUSIONS
Sleeping bags are an essential piece of equipment. Choosing the correct one can make or break an adventure. In simple terms, a good nights sleep allows you to rest and recover for the next day’s demands.
Nobody likes being too cold, especially at night, so keep this in mind and embrace the layering system.
Understand that we are all individual, what works for one, does not work for all.
Research the race and environment you are racing and check the highest and lowest temperatures. Start looking at sleeping bags with the appropriate *comfort rating and narrow down a search from here.
Remember, not two places are the same! For example, there is a huge difference in the desert/ weather say for Morocco, Atacama and the Grand to Grand in the USA.
Also understand the specifics of your adventure and what bag best suits your needs. To clarify on this, if you are going to the desert and the Himalayas, you will need two sleeping bags as the demands are very different. However, if you are going to the desert and then going back-packing in France in summer, the same sleeping bag will almost certainly work.
A sleeping mat is a no brainer when it comes to sleeping. It adds comfort and a barrier between you and the ground. For example, in the Himalayas when the ground is frozen and hard, why would you not put a barrier between you and basically a hard block of ice.
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