One of the important items in your evacuation kit should be a quality sleeping bag. I know, I know, why invest in an expensive bag when "real men" can just roll up in an old army blanket and tough it out? I've heard that argument, and I've slept plenty of times in my favorite olive drag wool blanket.
First of all, not everybody in a survival situation is a "real man." Some are children, some are nursing mothers, others are sick and frail. So all you "real men" out there reading this, just go ahead and wrap up in some juniper bark if you want to. This information is for the rest of the world who might be interested in finding out how to go shopping for a suitable sleeping bag.
A sleeping bag should be rated for the season and conditions in which it will be used. It makes a difference if you live in Alaska or South Texas. Buy accordingly.
- A summer season bag is rated for 35 degrees F and higher.
- A 3-season bag will range from 10 to 35 degrees.
- A cold weather bag is rated for -10 to +10 degrees.
- A winter bag will be rated for -10 degrees F and lower.
There are 2 main fill types available in sleeping bags — down and synthetic insulation.
- Down is lightweight, packs smaller, offers excellent warmth and is still very breathable. Down bags are more expensive up front, but are durable and offer great long term value. They work well in dryer climates and for excursions where weight or pack size are important.
- Synthetic insulation is available in a variety of qualities, weights and pack size. Generally, synthetic fill is heavier than down, but less expensive initially. It also works well in wet, cold conditions, retaining body heat even when damp (whereas down loses insulating properties once wet). Synthetic bags are usually easier to clean than down bags.
- The efficient shape of the mummy cut requires less of your body’s energy to heat excess space. Mummy bags usually include fitted shoulders and a hood, which help to retain heat at critical locations.
- Rectangular bags offer a roomy fit, ideal for sleepers who move around a lot during the night. They also offer excellent versatility, allowing couples to create double-wide options, or opening completely for blanket style use. Because of the extra space and wide opening at the top, rectangular bags are less thermally efficient in very cold environments.
- Within these 2 shapes, there are variations. Some rectangular bags include a hood, which is usually a looser fit than a mummy hood. There is also a variation of the mummy fit, a semi-rectangular shape, that offers some of the thermal efficiency and weight savings of a mummy bag, with a little more room.
- Ensure that you’re getting a bag that fits your height. A good rule is to look for a bag that is 6” longer than your body height.
- Also note that many bags are offered in men’s and women’s versions. Generally, women’s bags offer shorter lengths and more proportionate shoulder and hip girths.
- Some heavier rectangular bags offer a durable cotton blend on the bag’s shell. While these materials generally don’t repel water as well, they do offer a cozy, roomy bag option.
- Liner materials should promote breathability, allowing your body moisture to disperse rather than become trapped inside the bag. Some of the most common liner materials are:
- Poly-taffeta – smooth finish and lighter weight. Usually cold to the touch upon first entering a bag, but warm up quickly.
- Pongees and brushed poly-taffeta – while a synthetic blend, they offer a soft feel and warmer entry into the bag than a plain taffeta.
- Cotton blends (poly-cotton, flannel, etc) – softest liner options, warm to the touch and breathable. Generally the heaviest liner options.
- Sleeping pad attachments — A sleeping pad will help insulate the bottom side of your bag, and add cushion. Look for a bag that is compatible with your pad, or has sleeping pad attachment loops.
- Zippers and anti-snag treatments – Some bags use a locking zipper slider, which helps hold the zipper in place even if you move around a lot during the night. Many bags also offer dual-sliders, which means there is a zipper pull at both ends. This allows you to open the zipper at the bottom of the bag, for additional venting near your feet. Look for anti-snag treatment on both sides of the main zip. There are many anti-snag techniques in the market, so if possible, test a bag before you purchase it, to ensure you’re comfortable with the ease and speed of the zipper design.
- Draft tubes – if you’ll be using your bag in colder temps, look for a bag with a draft tube the full length of the main zipper, and possibly around the neck. Draft tubes are filled with insulation and help to seal locations hat suffer higher heat loss.
- Ergonomic footbox – available more often on mummy shapes, an ergonomic design at the bottom of the bag allow a person’s feet to lay in their natural position.
- Stash pockets – purely a convenience feature, these pockets help keep valuables easily accessible.