Are You in the Market for a 0 Degree Sleeping Bag?

Using a bag with a 0 degree rating is for insulation during winter conditions. If you are looking for gear that will keep you warm in frigid temperatures, this is the article for you. We will dive into comparisons between down and synthetic and analyze the best types of down for sleeping in. The article will end with a recommendation of what we see as the premiere down sleeping bag - not a paid advertisement!

Down or Synthetic?

Warmth to Weight Ratio. Down is made from feathers, naturally occurring, they are compressible and lightweight. Synthetic is made from polyester fibers which do not insulate as well or compress as tightly. Insulation relies on how much air can be trapped between the user's body and the external elements. For a synthetic sleeping bag to have the same temperature rating as a down bag, it would have to be bulkier and heavier, requiring more material.

How Water Affects Down and Synthetic. Down has no oils protecting it from moisture. When the feathers get wet, they crumple down and lose all loft. This can be a potentially life threatening situation on a winter camping trip. Inversely, synthetic materials do retain some insulation abilities because they are not as compacted by water.

Recently, manufacturers have been treating down with hydrophobic wax as a way to protect against such situations. The long term performance of treated down is still unknown but check out this video for a thorough analysis comparing the two types.

Price. Down will be more expensive than synthetic but when hypothermia is a concern, the additional investment is well worth it.

For winter camping, I will always recommend down over synthetic. Don’t be too afraid of getting your bag wet, simply prepare for it. I carry my sleeping bag in a waterproof ultra-sil Sea to Summit bag. If you are taking it on a rafting trip, I would recommend using a more heavy duty dry bag to protect against full submersion.

Measuring Good Down

For sleeping bags, you will want the highest possible rating, either 850 or 900 - again, this will not be easy on the wallet but it will save your life in arctic conditions. The benefit of higher fill power is that less material is needed, making the bag lighter and easier to carry.

The Ethics of Down

If you simply can’t stand to use animal products, then down is not for you. The material is sourced by killing ducks or geese, then plucking them of their feathers. Generally, the less money spent on an item, the greater the chance animals were killed inhumanely. Maintaining animal welfare cuts into the profits of companies and ultimately, the choice is up to the consumer on who to support.

Luckily, there is an organization dedicated to tracking and maintaining ethical standards across the industry. Responsible Down is the best NGO available to determine responsible consumerism. When buying a sleeping bag, look for their seal of approval, if this is an issue you care about.

Properly Using 0 Degree Down Sleeping Bag

Mummy cut only. For winter camping, only one design will suffice, that is the mummy cut. Any other cut will leave too much room for air to escape. Also, stay away from quilts when utilizing sleeping systems for 0 degree temperatures. Their open back design leaves too much room for error, even a couple minutes of exposure can destroy hours of hard work warming up a bag.

Water resistant material. The outside material of your sleeping bag should be highly water resistant. This will help repel any liquids that may find their way toward the bag.

Always use a sleeping pad. Down does not insulate when it is compressed. Any part of the bag that is crushed between the ground and your body is wasted. When experiencing below freezing temperatures, use well insulated sleeping pads to compliment your sleeping system. Without a pad, the ground will suck heat out of your body, regardless of how awesome your sleeping bag is.

Temperature Rating. A good rule of thumb is to add 10 degrees to any temperature rating on a sleeping bag. I do this to measure comfort, not survivability. If it’s going to be 10 degrees at night, a 0 degree bag will keep me nice and toasty. If it does fall to 0, I will choose to bring a silk liner and even sleep in my rain gear to protect against the temperature.

Feathered Friends Snowbunting Ex 0 Sleeping Bag

My favorite sleeping bag company is Feathered Friends. They use only the highest quality down, all of it ethically sourced. Manufactured in Seattle, their products withstand the test of time. I have been using their bags for over 5 years without them breaking or losing loft. The craftsmanship on these bags are excellent, and I have no problem recommending them for life threatening situations.

Things I like about this bag

  • Fill power. Using 900+ goose down is almost unheard of. This amount of loft is truly insane and will keep you warm.
  • Over all weight. Finding a 0 degree bag that weighs under 3lbs is not an easy task. Weighing in around 2lb 13oz makes carrying gear into the backcountry a much easier proposition.
  • No frills design. There are no extra pockets or hydrophobic down with this design. Simply a sleeping bag, designed to keep the user warm. Minimalism at its finest.

Things I don’t like about this bag

  • Price. Selling for $599.00, this is not a cheap investment.
  • Tight fit. If you are a larger person carrying around a few extra pounds, the mummy cut is unforgiving. They do offer a wider bag, the Ibis Ex, in case you need a few extra

Specs of the Snowbunting Ex 0


Mummy Cut

Outside Material

Pertex Shield EX Waterproof/Breathable

Lining Fabric

Pertex 30 Denier Nylon Taffeta

Temperature Rating


Fill Power

900+ Goose Down

Average Weight

Reg 2lb 13oz

Long 2lb 15 oz


Reg 6’0”

Long 6’6”

Dimensions - Shoulders, Torso, Feet


 0 Degree Sleeping Bag Summary

When choosing a winter sleeping bag, prioritize your decision based on warmth. Down provides the best material for that purpose and understanding why it’s superior and how it works will help in maintaining your new investment. Freezing to death is a terrible way to go out, use the right gear to match the conditions.