Many sleeping bags also come with a ‘comfort limit’ for guidance on the lowest temperature in which you should be able to have a comfortable night’s sleep. We recommend buying a sleeping bag that offers a comfort limit slightly lower than the temperature you are expecting to sleep in to give yourself a couple of degrees as insurance, should the mercury drop lower than anticipated.
We use three temperature ratings to show you the range of comfort for each sleeping bag. The upper figure we refer to as ‘Comfort’, the middle figure is ‘Limit’ and the lower is ‘Extreme’. These ratings are based on recommendations by the European Outdoor Group and are described as follows:
Comfort - The temperature at which an adult female can have a comfortable night’s sleep.
Limit - The lowest temperature at which an adult male can have a comfortable night’s sleep.
Extreme - A survival rating for an adult female; after eight hours hypothermia may set in.
There can be huge variances between people in the way they sleep and how susceptible they are to the cold caused by a number of factors such as gender, age and weight. This should be taken into account when choosing your bag. Down bags generally offer a larger guide range because they tend to be less clammy than synthetic equivalents, so are more comfortable in warmer temperatures.
Tip: If you know you feel the cold, opt for a sleeping bag that offers a little more warmth than you think you’ll need. It’s easier to cool yourself down than it is to warm up.