One of your top priorities in emergency equipment should be a sleeping bag. Not only is it important in a bug-out scenario, but in the chill of winter your own home can turn into a hypothermic environment. In terms of the three needs of survival – food, water and shelter – sleeping bags are a key component of the latter.
If you’ve ever shopped for a sleeping bag you’ll notice that you can spend anywhere from $20 to $600 with temperature ratings from -50 to +50. So what’s the difference between these bags and how do you know which is right for you? Well I’ll tell ya:
Temperature Rating
The temperatur rating of your sleeping bag is your primary concern when shopping. It doesn’t matter if it’s light or heavy; synthetic or down if you’re freezing to death. The temperature rating of a sleeping bag defines the lowest temperature you can be sleeping in with the bag and remain comfortable. The ratings are based on the assumption that you have both used a sleeping pad underneath the bag and are wearing long thermal underwear to bed. A word of caution – the method of determining the temperature rating varies from manufacturer to manufacturer. Because of this, you should always take them with a grain of salt and never assume they are guaranteed.
Choosing Your Temperature Rating
As we discussed earlier, the temperature rating is a ballpark and cannot be depended on. To decide on the right temperature rating for you, find out the lowest temperatures of the year in your area and the same in the areas you intend to bug out to. Select a bag with a temperature rating around 10 degrees Fahrenheit lower than your lowest annual temperature. You can always vent your bag if you get too warm.
What Else Effects Your Warmth
- Contour of the Bag – Sleeping bags work by creating an insulated area of “dead air” around your body. Your body heat warms this dead air and the bag retains that warmth around your body. If you have a bag with lots of extra space around your body, you’ll have more air to warm.
- Clothing – What you wear has an astounding impact on how warm you will be in your sleeping bag. On a typical night expect to wear long thermal underwear and socks. In especially cold nights you can insulate your body further by wearing pants, a fleece jacket and a balaclava.
- Sleeping Pad – A sleeping pad is an essential add-on to your sleeping bag. Heat gravitates to colder environments. This means that if your body is directly on the cold ground, it will literally suck all the heat right out of you. A good sleeping pad keeps your body lifted off the ground, maintaining your body temperature.
- Tent – A solid tent just becomes one more layer of insulation between you and the elements.
- Genetics – Some of use just happen to be “hot” or “cold” sleepers. I sleep on top of the covers with a fan blowing on me all winter long. I, however, am not the typical. Most women are “cold” sleepers and thus require a lower temperature rated sleeping bag to remain comfortable.
Construction
Filling
There are two different kinds of filling down and synthetic. Each has it’s pro and cons.
Down (Goose Feathers)
- Lightweight
- Compressible
- Durable
- Breathable
- Expensive
Synthetic (Polyester)
- Quick Drying
- Keeps Insulated When Wet
- Durable
- Nonallergenic
- Affordable
Shell
The outer layer of the sleeping bag is known as the shell. Common fabrics for the shell include nylon and polyester. The only thing you need to worry about concerning the shell is that it is water resistant. Test this by taking a wet wipe and rubbing the outside of your bag. If the moisture beads up (instead of soaking into the fabric) you’re good to go.
Shape
As mentioned earlier, the purpose of a sleeping bag is to create dead air around your body. This dead air is warmed by your body heat and retained with the sleeping bag’s insulation. This means you want as little dead air to heat up as possible.
Larger bags will provide the maximum comfort. Allowing you to move freely and sleep more naturally. So if low temperatures aren’t an issue for you, a rectangular bag might be a better fit for your needs.
Rectangular
- Roomy and comfortable
- With compatible zippers, rectangular bags can be combined for family/couples use as a double-wide bag
- Good for warm weather sleeping
- Non-contoured – will not warm as quickly or stay heated as easily
Mummy
- Contoured – optimal for cold weather
- Lightweight
Accessories and Special Considerations
Families and Children
If you have a small child, they won’t produce nearly as much body heat as you. Instead of purchasing them a separate bag, you can save space and keep them warmer by buying two bags that can be combined by zipper. This way you can sleep the whole family together, keeping each other warm.
Liners
A sleeping bag liner serves multiple purposes. First, it protects the inside of your bag from damage due to sweat and regular wear and tear. It also keeps the inside of the bag clean. Finally, it adds an additional layer of insulation. Using a sleeping bag liner can increase the temperature inside the bag by 10 to 15 degrees. On warmer nights you can even get away with foregoing the sleeping bag and just sleeping in the liner.
Dual Bag and Pad Systems
Some manufacturers (such as Big Agnes) provide sleeping bag systems in which the bag and pad are integrated. These are nice because they reduce the weight to carry both and provide the added convenience of not having to worry about rolling off your mat.
So head on over to your local camping retailer and start shopping for your sleeping bag like a pro!
