A sleeping bag is something most campers buy once in about ten years. If you’re in this group then it’s important to choose the right sleeping bag from the very beginning. Unfortunately there is no one sleeping bag that’s right for all conditions. One that works best in cold weather may be a nightmare near the equator.
The Four Shapes of Sleeping Bags
You should not base your decision the shape of the sleeping bag but it may affect their ability to keep you warm a little bit.
Mummy Bags – This is the most popular shape of sleeping bag and the most effective in cold weather. As the name suggests, it looks like a bag made for mummies (not mothers) – wide at the body and tapers at the legs. This provides a close fit for your feet as well as your body which makes it effective in keeping in your body heat. Mummy bags usually have strips filled with fabric sewn along the zipper. This is called the draft tube and it helps prevent the heat from escaping through the zippers. Some people may feel claustrophobic inside this tight fitting sleeping bag.
Rectangular – This is the shape of the first sleeping bag. It came from the idea of sewing two blankets together. They’re quite heavy and bulky but it gives you a lot of room for your feet and often provides a good cushion against the hard ground. Two of these sleeping bags can often be zipped together for more space. Ideal for people who suffer from claustrophobia.
Barrel – This is an oval shaped sleeping bag, which is more effective in keeping you warm than the rectangular shaped sleeping bag but not as effective as mummy bags. If you use this in cold climates like in the mountains you would need to wear a beanie or balaclava because a hood is usually not provided.
Synthetic Sleeping Bags – They come in different names like Polarguard, Thermolite etc, depending on the brand. Manufacturers are pushing the limit in designing synthetic fibers that would make the ultimate insulation for sleeping bags . They get lighter, fluffier and more compressible with each new improvement and will soon outdo down sleeping bags . Synthetic filled sleeping bags retain their insulation properties even when wet and they’re relatively easy to clean and dry. Micro-sanded polyester gives you the feeling of sleeping on silk.
Down Sleeping Bags – Despite the improvements in synthetic fibers, down is still the best fill for sleeping bags . They’re lighter and packs down smaller. They’re also fluffier, which makes it ideal for keeping you warm. If you take care of it well it can last for 20 years. Synthetics bags don’t last this long but down don’t retain their insulating properties when wet and they can take a couple of days to dry properly. Down ratings of 600 to 650 are of excellent quality but 800 to 900 fills are so effective that it can make you sweat even in sub-zero temperatures. They’re also very expensive compared to synthetic sleeping bags .