When the temperature gets down in to the sub zero range it takes a very specific kind of backpacking and camping gear to keep you comfortable and safe from the weather. In particular, you need a sub zero sleeping bag. Cold temperatures can be dangerous if you’re not prepared, and sub zero sleeping bags are one of the more important items needed to ensure that you stay safe. Of course you should also have other items, like a good sleeping pad, to compliment your sleeping bag.
Sub Zero Sleeping Bags
What to look for when buying a sub zero sleeping bag.- Water Resistant – Whenever you’re camping or backpacking near a lot of moisture, whether that be rain or snow, it’s worth investing in a water resistant sleeping bag. Down does very poorly as an insulator when wet, and synthetic insulation does better, but still not 100%. So it’s important to keep your sleeping bag insulation dry if you expect to stay warm.
- Shape – When you get in to the sub zero temperatures you need to squeeze every degree of warmth from your sleeping that you can, and a rectangular sleeping bag is never going to be as warm as a mummy shaped sleeping bag, just because there is less space to heat inside a mummy sleeping bag.
Best Sub Zero Sleeping Bags
Some of the very best sub zero sleeping bags for cold conditions.- Rab Expedition 800 - With a minimum temperature rating of -9, this is a great sub zero sleeping bag for that range of temperatures just below the 0 mark. It uses 850+ fill down, which is high quality, and a waterproof, breathable exterior to keep the down dry. It has a tight alpine mummy cut, but does have enough room for you to wear a few extra layers to bed, so add a few degrees of warmth if the temperature dips down unexpectedly. And at 3 pounds 6 ounces, or 1.54 kilograms it's solid, lightweight option.
- Mont Bell U.L. Super Spiral Down Hugger - This sleeping bag from Japanese manufacturer Mont Bell is good down to -20, and weighs just 3 pounds 7 ounces, or 1.55 kilograms, which is less, you'll notice, than the already lightweight Rab sleeping bag above. The exterior of this sleeping bag is only water resistant, however, and the down is a slightly lower quality 800+ fill. Still, an excellent option if you're looking to save on weight.
- Marmot CWM EQ - For those really, truly cold conditions, the CWM, with a minimum temperature rating of -40 is the sleeping bag you want. The exterior is waterproof, and the down is a decently high quality of 800+ fill. Thoughtful features like a reinforced footbox, to handle a water bottle kept warm for morning, help to separate this sleeping bag from the rest. And the impressive weight of just 4 pounds 10 ounces, or 2.09 kilograms certainly doesn't hurt.