Types and Styles - Sleeping Bags for Camping
The key components of a sleeping bag are:
- its Size and Shape;
- its Outer Shell (the outside of the sleeping bag) (see Materials Used);
- its Fill (the crucial component that actually keeps you warm) (see Materials Used);
- the Zip/Opening (see Materials Used),
You need a sleeping bag that will fit you comfortably without either being too tight or leaving much surplus space.
If the sleeping bag is too tight, the insulating material may become too compressed around your body and this will reduce its effectiveness. Surplus space adds weight and is difficult to keep warm.
Some manufacturers also include a woman's fit in their range - to accommodate narrower shoulders, broader hips and a generally cooler sleeping body temperature. Though in our opinion, it's debatable whether these refinements really make that much difference.
The most common shapes are Rectangular or Mummy. You can also find a variant of the rectangular sleeping bag that incorporates some narrowing at the foot end.
Mummy sleeping bags are wider at the top and narrower at the feet end. Because they are most similar to a person's shape, they are also the most efficient in keeping you warm for the lowest overall weight. Although some may find them a little claustrophobic, these are the best option for most purposes.
Rectangular sleeping bags are usually wider at the top and the same width all the way down to the bottom. This gives more room and so you'll feel less claustrophobic - however this style of sleeping bag is overall less efficient at keeping you warm and tends to be heavier than a Mummy shaped sleeping bag.
However, Rectangular sleeping bags are easier to zip together to form a 'double' sleeping bag and can be opened out completely for use as a blanket.
Semi-Rectangular sleeping bags (rectangular at the top but tapering to the foot end) are a compromise - but these tend to have all the disadvantages of Rectangular sleeping bags with none of the advantages.
Because most heat loss is from the top of you head, most sleeping bags will also incorporate a hood that can be closed tightly in very cold conditions.
Sleeping bags designed for use in colder temperatures will include a collar (aka shoulder baffle) at the bottom of the hood. This is there to prevent heat loss from around your neck and shoulders.
Hoods and shoulder baffles also give you a few more options for 'venting' the sleeping bag without actually having to undo the main zip.
It's important that your feet are well accommodated in your sleeping bag so there is usually a flared, boxed area (aka foot box) at the bottom of the sleeping bag.
In some sleeping bags designed for high mountain use, this area will be big enough to fit a hot water bottle and/or even your boots.