Consider these points before buying a sleeping bag, and when you have, check out six of the best sleeping bags for winter here.
Manufacturer temperature rating
A sleeping bag doesn’t provide warmth; it minimises heat loss by trapping body heat. Designed for a sleeper wearing a base layer, a hat and using a sleeping pad, the ratings give an idea of insulation ability. Unless you’re climbing Kili, forget extreme ratings such as -27°C. For South African conditions, go for a three-season bag suitable for use from spring to autumn.
Shape
Rectangular envelope shapes offer more room to move if you don’t like being restricted. A mummy-shaped bag is warmer.
Weight
You’ll want the lightest possible bag if you’re hiking. Down is best in terms of weight-to-warmth ratio.
Filling facts
Goose down
If money’s no object, goose down wins as the finest quality insulator. It’s lightweight and maintains its loft (heat- trapping power) longer than synthetic materials, which are susceptible to breakages after years of use. Look at the fill power measured in inches cubed: 400-450in3 indicates medium quality, 500-550in3 is considered good, 550-750in3 is great and more than 750 in3 is excellent. Then, look at the ratio of down to feathers: 90/10 means 90 percent down and 10 percent feathers. An 85/15 ratio will be cheaper, but retain less heat. The downside of down? If it gets wet, the insulation flattens and becomes matted, losing all loft. Goose down requires special cleaning products that don’t strip its natural oils or affect loft (down wash costs R80 at Cape Union Mart).
Hollow fibre
A common and affordable synthetic insulator for the traveller who doesn’t have the money for down or doesn’t expect to camp in low temperatures. Shreds of synthetic fibres imitate the heat-holding abilities of down, but don’t match its warmth ratings. Synthetic fibres don’t absorb water and dry rapidly.
Microfibre
Another synthetic option, it’s less bulky than hollow fibre bags, compresses better and is great for hiking or when space is at a premium. Almost all microfibre bags are mummy shaped.
Storage
The compression sacks that sleeping bags come in are for travelling only. When not in use, store them on hangers or folded up like a duvet because extended time in compression sacks breaks synthetic fibres and eventually the insulation abilities dwindle.
Travel tip
Most sleeping bag linings are synthetic, which can make for sweaty sleeping. Use a cotton liner because it can be washed keeping your bag clean and odour free. It’s also great for summer trips when an insulated bag is too hot.
Clever camper
The First Ascent Pack Pillow is a great sleeping bag extra – instead of wasting valuable packing space, fill this case with washing or a towel to use as a pillow (you could also use an empty pillow case).