Sleeping Bags

Sleeping bags are available in a variety of different shapes, quilting designs and fills, and there are even some home-industry manufacturers who will make them to order. Cheap sleeping bags have a poor quality fill and the stitching for the quilting may go right through the bag so there is a minimum of insulation in these areas. The most popular filling for general use is hollow-fibre, which also provides some warmth even if the bag gets wet. It is supposedly washable (but should not be spin-dried), although experience shows that the bag's thermal insulation deteriorates with each wash.

The best filling by far is goose down, but high-quality down is very expensive and these bags must not be allowed to get wet! The biggest advantage of down is its lofting ability, which means that a down bag can be compressed to a significantly smaller volume than a hollow fibre one of the same warmth, or - for the same compressed volume - a down bag is significantly warmer.

A cheaper hollow-fibre bag is usually sufficient for most year-round conditions in the lower berg, especially with the use of an additional thermal liner in winter. Your can still wear more clothes to make up for any shortcomings! For winter hikes on the escarpment you would be wise to invest in the warmest down sleeping bag you can afford, and supplement this with a good thermal liner. Many experienced hikers therefore have a "summer" and a "winter" sleeping bag, and keep their warmer one for the more serious escarpment hikes.

Strangely - perhaps because of the manufacturing process or to facilitate washing - most sleeping bag manufacturers insist on providing a zip - usually full-length - down the side of the bag. Very few people ever seem to make use of this zip, and it is often more of a nuisance than anything else. A quality zip (e.g. YKK) adds considerably to the expense, not the least because of the baffle which must be stitched to the inside of the bag to prevent heat-loss through the zip. The baffle must also have a fairly rigid facing to prevent it from becoming caught in the zip when this is used, and also to keep it in place.

Most sleeping bags available in South Africa have a comfortable cotton lining, but good quality down bags are often lined with synthetic fabric, for two reasons:

• Since down is extremely difficult and expensive to clean properly (it should never be dry-cleaned!), a liner is usually used to reduce washing requirements. A synthetic thermal liner can also increase insulation considerably. A liner is far easier to slip into a sleeping bag if the latter is lined with a nylon-like fabric.

• In cold weather you will be wearing at least one layer of clothes inside your sleeping bag, so even without a liner your skin will not come into contact with the bag's synthetic lining. There is therefore no issue regarding comfort under these conditions.

Sleeping bags come in three basic shapes:

• Rectangular: these are really camping bags and are more suitable for "indoor" use (e.g. caravan or camping tent). They are not "worn" in the same sense that a more serious sleeping bag is worn, since they are big enough for the user to turn over inside them.

• Cowl-top: these are modified rectangular bags with a "hood" which can be pulled tight via a draw-string around the head. They have more than ample leg and foot space, but this is their main disadvantage in cold weather, where this additional insulation and volume could be put to better use elsewhere.

• Mummy: similar to the cowl-top, this type of bag is tapered towards the feet. A mummy is worn much like a piece of clothing, so it fits snugly around the torso and legs like a tube-shaped jacket. When the user rolls over, the whole bags rolls with him / her. An essential part of the mummy is it cowl, which can also be drawn tightly around the face with a draw-string. Most mummies, and some cowl-tops, have an additional draw-string to pull the bag tightly over the shoulders as well, but if you suffer from claustrophobia, getting out of one of these bags in a hurry if both the cords are drawn tight could result in insanity!

Features to look for when buying a warm sleeping bag:

• Low total weight but high thermal insulation

• Cowl-top or mummy design with a good, strong draw-cord

• As short a zip as possible (preferably none!) with a good baffle that doesn't get caught in the zip when this is used

• Rip-stop nylon outer

• A cotton inner lining is preferable for a summer sleeping bag, but nylon is probably better for use with a thermal liner in winter.

Your sleeping bag should be considered a survival item - especially in winter - and should be treated as such. Never carry it on the outside of your backpack; rather keep it in the bottom of the upper, main compartment of your pack where it will usually be the last item you remove at the end of the day. Avoid getting it dirty, since every wash reduces its insulation a little further.

Last modified on 2011/11/10