The freedom to camp wild beneath the stars is one of the principal attractions of many of our Sweden holidays, whether you are stretched out at the water’s edge on a timber rafting tour or camping in a tipi in the depths of winter on our Dog Sledding and Winter Bushcraft experience.
Having a good night’s sleep is central to your enjoyment of any outdoor holiday, and in this article we give an overview of points to consider when choosing a sleeping bag.
Rectangular or “mummy” bag?
Rectangular bags are comfortable and spacious, and have the advantage that you can open them out to use as a cover. However, such bags are mainly suitable for use in youth hostels and perhaps cabins in summertime. For camping or lower temperatures, a “mummy” bag will provide much better insulation.
Bags with tapered profiles are also available, offering some of the comfort of a rectangular bag while preserving some of the insulating properties of the “mummy” shape.
How a sleeping bag keeps you warm
A sleeping bag keeps you warm by trapping a layer of air which is then heated by your body. This seems an obvious point, but it is very easy to forget the less obvious implication: it is essential to be warm when you get into your sleeping bag! Your bag will not warm up properly if you get into it when cold.
Therefore, if you’re feeling cold before you turn in for the night, jump around and do some exercise and make sure you are feeling warm before getting into your bag. In cold weather, “doing the penguin” can be a good way to warm up (silly, but effective). Put your arms by your sides with your palms facing the floor and your fingers pointing out at right angles. Shrug your shoulders vigorously for a few minutes and you will feel the blood pumping to your extremities. A good way to warm up cold fingers! Having a hot drink while inside the bag is also an excellent way to warm up both you and your sleeping bag.
Should I choose down or synthetic insulation?
Each has its advantages and disadvantages. Down is an excellent insulator and is often the preferred choice for cold-weather bags. It is also much lighter than synthetic materials and has very good lofting properties, meaning that it can be compressed tightly and will still expand well. A down sleeping bag will generally have much better warmth-to-weight ratio than a synthetic bag. A good down bag will have at least 85% down and top quality bags may have 95% or more.
On the down side (!), down bags are generally more expensive than synthetic fillings. They are also unsuitable for wet or humid climates, as they take a long time to dry properly and lose almost all their insulating properties when wet. Your breath contains a lot of water vapour, and burying your head completely inside the bag may make it damp and cold from the inside. It may be better to sleep with your face exposed and wearing a hat or scarf. Ensure that you air your sleeping bag properly the following morning before packing it away for any extended period.
If you are buying a down bag, bear in mind that there are some animal welfare issues to be considered regarding the production and harvesting of down, so make sure your preferred manufacturer uses ethically-sourced fillings.
The technology used in synthetic fillings is improving all the time, and many people choose a synthetic bag as their preferred option. Materials such as Primaloft offer many of the advantages of down with the convenience of a synthetic bag.
Synthetic fillings are normally made from polyester filaments or sometimes fibre-pile. They retain much more of their insulating properties when wet and so are ideal for rainy or humid climates. They are easy to care for and clean and are normally more affordable than an equivalent-rated down bag.
However, synthetic bags generally have the disadvantages of being heavier and bulkier and may also have a shorter useful lifespan.
What do the temperature ratings on sleeping bags mean?
How you feel and react to the cold will vary enormously depending on your body, your energy level, your mood and many other things. The combination of these different factors means that while one person may be warm and comfortable in a particular bag, another person (or even the same person on a different day!) may feel chilly.
Many bags are rated with both “Comfort” and “Extreme” temperatures, which can be misleading. You may find that even if the label on your sleeping bag says “-20 degrees” you would feel very cold indeed using the bag at this temperature!
Bear in mind also that temperature ratings are sometimes calculated differently between manufacturers, and will be based on certain assumptions regarding how the bag is used, such as that you are using the bag with a suitable sleeping mat for insulation from below.
What should I think about when buying a sleeping bag?
When deciding which bag is most suitable for you, you should bear in mind the following:
- What will you use the bag most for? You should choose a bag suitable for the situations and temperatures in which you will most commonly use it. If you only go camping in cold conditions very rarely, a lighter bag can be upgraded by placing it inside an extra bag or using a thermal liner, but a polar bag will be uncomfortably warm outside the depths of winter!
- If you know that you feel the cold, choose a bag with a rating higher than you anticipate needing.
- Consider whether weight and/or bulk are important considerations. If so, you may want to opt for a down bag, but bear in mind that these are less suitable in damp conditions.
In the next article, we will be looking at options for sleeping mats and sleeping bag liners. In the meantime, sweet dreams!
The Nature Travels Team