Deciding on a sleeping bag
Having bought, borrowed, slept well/badly in, been too hot/cold in, and now designed and manufactured sleeping bags, it seems to me that the “right” sleeping bag is a compromise between numerous, highly subjective considerations. So whether you are buying your first or your fifth sleeping bag, you might like to bear the following in mind.
Buy a good one
A good-quality sleeping bag is one of the most expensive items you can buy, but as you can expect it to last up to 30 years, it is definitely worth spending the money. You should never have to replace it.
Buy a versatile one
Since a sleeping bag is likely to be one of your most used items of outdoor equipment, it makes sense to buy one that is versatile. A sleeping bag with 500 g of down fill is a great all-rounder until you start looking at trips to the Andes and the Greater Ranges, or the Alps in deepest winter. A bag with 700 g may be a little warm for summer in Scotland, but can accompany you up to 6000-7000 metres, depending on your tolerance for the occasional night of discomfort. Anything over 700 g of fill is likely to be your second bag, i.e. one that you are buying for a specific destination and end-use, as it would be too warm (and unnecessarily heavy) for normal (i.e. less extreme) applications.
Be fussy about performance
Sleeping-bag performance is generally quantified in terms of temperature ratings, about which we have more to say elsewhere. The most important factor from this point of view is the amount of down fill. If you are comparing different bags containing more or less the same weight of down, and the down is of comparable fill power (give or take 100 FP), then their performance should be fairly similar. Beware of bags making claims significantly outside the standard bounds of temperature ratings.
Be realistic about temperatures
Temperatures experienced by climbers on expedition are often exaggerated. Yes, I’ve spent a night alone in an open bivouac at 7000 metres and I’m quite sure it was -25ºC. But to be honest, I probably can’t tell the difference between -15º and -25º: they are both cold. In reality, the only places that are extremely and consistently cold are the northern latitudes in winter and high altitudes. In short, don’t buy a bag that is warm for one or two really cold nights but far too hot the rest of the time.
Be realistic about weight
Ultra-lightweight bags may appear attractive, but they are not without drawbacks. Firstly, they will not be waterproof or water-resistant. Secondly, the zip – if they have one – may be lightweight, with consequences for performance. Avoid such zips, as they fail quickly. Thirdly, the fabrics used are not robust – just about all the climbers I know have a duct-tape patch somewhere on their bag.
Be realistic about yourself
When choosing the “right” sleeping bag, the manufacturer’s design criteria are only part of equation; it is just as important to factor in your own performance parameters. How much misery are you prepared to endure by going out with a lighter bag, for example? How much food will you be eating and will your body energy output be sufficient to warm your bag? How long are you going to spend on a route and what kind of shelter (mountain hut, tent, bivouac bag) will you have? What ground insulation will you have? What is the air humidity of the place and altitude you will be in? Depending on your answers, you will be better suited with a lighter or heavier, waterproof or non-waterproof bag.
We would like to build a page listing mountain ranges around the world and the sleeping bags people have used there (e.g. down fill, shelter and ground insulation, season, conditions and temperatures). If you would like to tell us about your experiences and are happy for these to be shared, please email carol@odl.uk.com.
