Choosing a Sleeping Bag

Just like people, sleeping bags come in all sizes and shapes.

Size

The unisex Badger mummy bag comes in two sizes: 6' 6" and 7'
You want a sleeping bag that is big enough for comfort, but not so big that you are carrying unnecessary poundage in your pack. Dead space in a sleeping bag is difficult to keep warm. Extra room takes more calories to heat, so your body has a more difficult time keeping the bag warm. Also, insulation tends to get compressed if your bag is too tight around your body. Once it is packed down, it won't work efficiently.

It used to be that there was not much choice in bag length, but now they come in all increments. Select a bag that gives you several extra inches of length in both the bottom and top–so you can stretch–but no more.

Shape

A current debate rages over the need for women-specific bags. Some companies make the argument that bags should fit bodies, regardless of sex, while others contend that women's broader hips, narrower shoulders, and colder sleeping temperature necessitate differently cut bags.

Mummy bags, which are cut wider at the shoulders and narrower at the feet, are the most efficient (for both sexes), in terms of weight and warmth. Since the bag conforms more closely to the human shape, sort of like a sarcophagus, the space is warmed using minimal body heat. However, if you have a tendency toward claustrophobia, or like to wriggle around in your sleep, a mummy bag might be too restrictive.

Rectangular bags have more room to toss and turn, but aren't as efficient for warmth. Because of the larger top opening, heat can escape more easily.

Semi-rectangular bags are a good compromise, with a tapered foot (roomier than a mummy) and contoured hood, and additional space at the torso for comfort.