Warmest sleeping bag in the world

Morning guys - I recently (19-21 June) hiked the Berg (with a fantastic guide if I may add - Deon from Berg Adventures ) and realised that I am a very cold sleeper. No really, VERY cold.

I have been told by numerous people to sleep ONLY in thermals and socks … however I could not bring myself to sleep in so little clothing. Having said that, I slept in six layers at the top and two at the bottom the one night after freezing my backside off on the 1st night.

Nevertheless … it seems of utter importance that I get a much warmer sleeping bag than what the company we are hiking Kili with can offer me … so …

I am thinking of buying a First Ascent rated -15 to -20 sleeping bag. Would there be anyone on this forum that regularly hike extremely cold places that would want to buy it over from me after having used it for only 7 nights? Happy to negotiate a resale price after the trip. I will off course use a liner too - which I will hold on to.

Yes, that is how warm I want to sleep.

I have been told by numerous people to sleep ONLY in thermals and socks … however I could not

If you’ve never tried it, we’re here to tell you that sleeping outside in the winter is way more fun than it sounds. That’s thanks to huge advancements in tech and design that make today’s winter bags more like portable nap spas than down survival sacks. We tested 17 different cold-weather cacoons to find the warmest, most breathable, comfortable, and packable options on the market. These seven bags put our testers into deep hibernation, even when temps dropped below zero. The challenge was waking up the next morning to face the cold.

At a Glance

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Best for Extreme Cold

Marmot CWM -40

$929 at Backcountry$949 at Marmot

Weight: 5 lbs (Regular)
Sizes: Regular, Long

Pros and Cons
⊕ Warm down to -40
⊕ Tough exterior fabric
⊕ Side zippers for arms
⊗ Overkill for the Lower 48
⊗ Heavy

“There is a lot to care about this -40-degree bag, one being that it will preserve you warm in -40,” says Alaskan dog musher, guide, and snowboarder Jody June Potts. That means somet

RADICAL 16H - THE WARMEST SLEEPING BAG IN THE WORLD

Can the best sleeping bag in the world be selected from hundreds of options? Yes, it can - it's the Radical 16H. How do we know this, i.e., how the temperature range of a sleeping bag is tested and what determines that one model is warmer than another, you will find out from today's text.

WHAT WILL YOU LEARN FROM THIS POST?

• Is Revolutionary 16H the warmest sleeping bag in the world?
• How are the parameters of down determined?
• Why execute down sleeping bags provide warmth?

IN BRIEF

Construction-wise, Radical 16H outshines the competition. Filled with the most highly regarded down in the world from white Polish geese with a loftiness of 900 FP and enhanced with an IRL internal coating that reflects up to 50% of body heat, it allows you to survive even in extreme conditions: comfort temperature -31/limit temperature -43/extreme temperature -73. Not only is it the warmest expedition sleeping bag in the world, but it also has a sky-high compression ratio, so it doesn't take up much space in your gear. Additionally, it is incredibly lightweight, weighing only 1500 g.

WHY IS A SLEEPING BAG WARM?

Everyone experiences cold and warmth dif

In February, Nemo launched an odd-looking sleeping bag called the Canon -40, made for surviving the world’s coldest temperatures. The whole package looks like it was air-dropped from outer space. At the head end, the “Stove Pipe Tunnel Hood” looks prefer a periscope or snorkel sticking out of the fabric. Along the sides, the “Thermo Gills” look like, well, fish gills.

Nemo, a 19-person gear manufacturer from New Hampshire, has been on a roll lately with their designs for innovative camping equipment. First, there was a tent held up by pressurized tubes instead of aluminum poles. Then there was a uniquely-shaped sleeping bag, the “Spoon Series”, which hugs the human body beat than traditional bags. Now, the Canon -40 sleeping bag is winning awards from reviewers at sites and magazines around the world.

The day we talked with design director Suzanne Turell about the process of making the Canon, her office was hectic with prototypes for tent pole clips coming off the 3-D printer, and meetings with the design and engineering team operational on plans for products three years out.

Turell, a 33-year-old surfer and hiker, first became interested in outdoor gear as a kid while camping with

Ultra XP

The EN (European Standard) rating is a standardized test that aims to set measurable targets and standardize temperature claims for sleeping bags. It is crafted to help the consumer construct an informed decision by using independently derived temperature values. Each EN sleeping bag test has four temperature ratings: Upper Limit, Comfort, Lower Limit, and Excessive. The three most common ratings are the following temperature ranges: Comfort, (Lower) Limit, and Extreme.   

For these measurements, it is assumed that a “standard man” is 25 years old, 1.73 m tall, and weighs 73 kg; a “standard woman” is 25 years old, 1.60 m tall, and weighs 60 kg.    

• Comfort: the temperature at which an average woman can anticipate to sleep comfortably in a relaxed position.   
• Limit: the temperature at which an average gentleman can sleep comfortably for eight hours without waking up.   
• Extreme: the minimum temperature at which an average woman can tolerate severe cold exposure for six hours. There is a chance of damage to health (no danger of death from hypothermia, but frostbite is theoretically possible).   

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