Choosing the Right Sleeping Bag

We've spent thousands of nights in a wide variety of sleeping bags, temperatures and weather conditions in many parts of the world. We believe that the information available on sleeping bags should only be used as a guideline and that the best way to choose a sleeping bag is to be realistic about yourself and the uses to which your sleeping bag will be put. Below are a few thoughts based on our (and our many customers') experience.

Buy a Good Sleeping Bag

Sleeping properly is fundamental to proper physical and mental performance. Yes, down sleeping bags are expensive BUT they still offer the best performance available and a good one will last you many years, possibly a lifetime if cared for properly. There's an old saying that rings true in this case – 'buy cheap, buy twice'. Beware manufacturers who claim significantly lower temperature ratings than their competitors for similar bags.

Know Yourself

How warm you feel depends on many factors including gender, general health, diet and fitness. Do you feel the cold more than most people? If so, you may wish to compromise by buying a slightly heavier but warmer sleeping bag and save weight, if necessary, in another area of your kit.

Be realistic about where and when you will use your sleeping bag.

Do you really need to save 50g in weight but risk not getting a decent night's sleep? Are you prepared to suffer a little in order to save pack weight? Do you need to buy a 4-season sleeping bag suitable for temperatures well below 0°C when you won't use it beyond the summer in the UK? The key is versatility, this is why 2- and 3-season sleeping bags are popular; they are suitable for most people's needs in the UK who do not sleep outdoors in winter conditions. Many people who buy the warmest bags are doing so for a specific trip or expedition and accept the fact that the bag will generally be too warm for UK use. What kind of weather conditions are you likely to encounter (not all tents are totally windproof!) Do you have a good insulating mat to sleep on?  Up to 80% of your body heat is lost to the ground so a good sleeping mat is essential.

What do the 'seasons' ratings mean?

Giving definitive temperature ratings for sleeping bags is a tricky business. Season ratings are a good starting point for people in the UK as many people have an idea of the times of year that they will be sleeping outdoors. Seasonal ratings see quoted for bags being used at sea level, generally air temperature drops with increased altitude. The seasonal rating system we use is as follows:-

1 season - suitable for use in summer only (lower limit of +5°C or higher)

2 season - suitable for use from late spring to early autumn (lower limit of between +5°C and 0°C)

3 season - suitable for use through spring, summer and autumn (lower limit of between 0°C and -5°C)

4 season - suitable for use all year round but generally in winter conditions, too warm for summer conditions (lower limit of below -5°C)

How are the temperature ratings worked out?

There are a number of standardised measurements for rating the warmth of sleeping bags, the most important being EN13537 in Europe and ASTM F1720 in the US. The minimum standard recommended by the European Outdoor Group (the outdoor trade organisation) is the labelling of temperature values as shown below:

Upper limit - Highest temperature at which a standard adult male is deemed to have a comfortable night’s sleep without excessive sweating

Comfort rating - Temperature at which a standard adult female can have a comfortable night’s sleep

Lower limit - The lowest temperature at which a standard adult male is deemed able to have a comfortable night’s sleep

Extreme - A survival rating only for a standard adult female. After 8 hours, hypothermia may start to start set in.

Which temperature rating do we use?

We quote the EN13537 Lower Limit wherever possible as we believe this gives the most realistic information.  It is worth noting that this is a lower limit so you might wish to consider a warmer sleeping bag if you encounter these temperatures on a regular basis.