So winter is here again and for most people, this means varying degrees of extremely cold temperatures for the next couple of months-pun intended.
And don’t be deceived by the proverbial beauty of winter, for within this period are tales of wrenching experiences courtesy of the freezing cold conditions.
If you’re planning a camp this season, my guess is that you will be seeking out the best sleeping bag for cold weather. No doubt, good sleeping bags could be a lifesaver at night and in outdoor conditions when one needs to sleep and when the temperatures get terribly low.
In this article, we will look at the various factors to consider when choosing the best sleeping bag that meets not just the functional requirements but also your personal preferences.
Why Sleeping Bags are important
Sleeping bags are basically lightweight beddings designed in a tube form usually with a zipper to provide warmth for a user staying outdoors. It is popular among outdoor campers’ and people into other outdoor activities like hiking and mountain climbing.
Physical conditions like the weather are part of the major determinants of health so sleeping bags do more than keep one comfy, they actually preserve one’s health.
They can save a user from dangers of frostbite and hypothermia associated with very cold weather. Hypothermia is an abnormally low body temperature caused by prolonged exposure to cold.
In principle, sleeping bags work pretty much the same as quilt beddings; they provide warmth and thermal insulation through multi-layered textile. The designs for sleeping bags varies depending on a wide range of factors including the anticipated temperature, size, and shape.
The Anatomy of a Sleeping Bag
There are just a few major functional parts of a regular sleeping bag which includes the shell, the insulation materials, and the zipper.
The shell—the outer and internal surface fabric—houses the inner isolation material and protect the user from external conditions. They can be breathable or waterproof or durable water repellent (DWR) coated shells.
Other parts include the baffles, which are the compartments within the bag that controls the heat transfer; the hood for covering the head; and the foot box which especially keeps the feet warm. Some manufacturers provide stuff sack and storage sack for packing.
How to Choose the Best Cold Weather Sleeping Bag
When choosing the best sleeping bag that it’s suitable for you, there are a few things you have to consider. Some are fundamental like the temperature ratings while some others like shape and color are a matter of personal preference.
Probably the most debated aspect of sleeping bags is the type of insulation—that is, between the synthetic or down insulation. While down insulations, made from duck or goose feathers, are known to provide superior thermal insulation than synthetic, both have their pros and cons.
Down insulations have a superior warmth-to-weight ratio which means light bags can provide sufficient warmth whereas the synthetic insulations, usually made from polyester fibers, perform better in wet conditions.
They are designed to maintain a decent warmth-to-weight ratio and also be water resistant making them ideal for humid conditions.
Another factor here is the ‘effectiveness’ of the insulation measured by how many cubic inches one ounce of down can fill. This is known as the fill power.
Down insulation can have fill power ranging from 450 to 900; at the latter end of this spectrum, one can get more warmth from lighter insulation material.
Sleeping bags are often categorized by temperature conditions where it can be used. It is important to choose a sleeping bag with a suitable rating for your environment—one that does not make you too warm or leave you too cold.
This rating is similar to the rating for outdoor camping tents. It ranges from one-season sleeping bags to five-season sleeping bags where one-seasons are suitable for warmer climes and five-season sleeping bags are for the coldest and humid conditions.
One-season sleeping bags are suitable for typical night temperatures of 10 degrees Celsius or more. They are often used in warm summer seasons or late spring where one can anticipate coldest temperatures of about +4 to +5 degrees. They often come without a hood and can be completely unzipped.
Two-season sleeping bags are ideal from late spring, summer and early autumn periods usually with a night-time temperatures 5 degree Celsius or higher.
These are a bit more versatile than the one-season sleeping bags but are not ideal for temperatures below 0 degrees Celsius.
Three-season sleeping bags are best suited for spring and autumn seasons when nights can get very cold but not freezing. A night-time temperature of 0 degrees is normal.
However, three-season sleeping bags are the most common and versatile bags available as they can be used all year round, although one may have to leave it unzipped on the warmer nights.
Four-season sleeping bags are designed for the very cold conditions of winter and some really cold winter nights. As expected, this category of sleeping bag will get the user sweaty outside the winter season.
Five-season sleeping bags are like the SUVs of sleeping bags, designed to protect the user from adverse weather conditions in freezing cold and snowy nights. They are markedly more durable than other bags and are made with water-repellent fabrics.
You may find that some sleeping bags are not rated in the traditional ‘seasons’ ratings but by using a single temperature standard for normal sleepers.
This rating established under the European EN13537 standard rates sleeping bags based on comfort rating, extreme rating, uppers and sometimes lower limits of comfort.
The Comfort rating is based on the lower limit a 'standard' adult woman having a comfortable night's sleep.
The Lower Limit is the lowest temperature at which a standard man can have a comfortable night's sleep.
The Upper Limit is the highest temperature at which a 'standard' adult man is able to have a comfortable night's sleep.
Extreme rating is the minimum temperature at which a standard man can survive without risk of death from extreme cold. As an extreme survival rating, it is not recommended for general use sleeping bags. The best general guideline is usually between comfort rating and a lower limit.
The length and widths of sleeping bags should be considered when making one’s choice. It is important you have just enough space to move around and not too much to affect the warmth of your bag.
Just like the size, the shape of a sleeping bag is important to ensure you are comfortable in it. The two common designs are the mummy style and the quilt style.
Like it is called, the mummy style allows user tuck one’s head in like a mummy and provides more insulation around one’s head whereas the quilt style looks like a down comforter with a zipper.
There is also women’s sleeping bag which has a different shape. These are slightly narrower around the shoulder and wider in the hips. They also have more insulation than men’s sleeping bags since women normally generate less warmth compared to men.
The weight of a sleeping bag is important for packing and for hikers who have to carry them along on their journey. While a heavier bag tends to provide more warmth, a lightweight bag of less than 1 pound which provides adequate insulation is preferable.
Our Review 3 Great Sleeping Bags
Weight: 2 lb 12 oz
Temperature Rating: 10 degree
Shape: mummy style
Insulation: duck down
This sleeping bag from Outdoor Vitals is suitable for the harshest conditions of winter with an extreme rating of 0 degrees and a comfort rating of 10 degrees.
It has a duck down insulation with a fill power of 800 which makes it lightweight and durable. Not only is it lightweight, but the bag is also super-compressible and as such an easy packing for your hiking and outdoor activities.
When compressed, the bag can take up as little space 11 x 8 inches and it also comes with a 4 point compression bag.
The outer shell fabric is coated with water-resistant—part of the VitalDry DWR technology for warmer and drier outcomes.
If you’re up for a durable, lightweight sleeping bag which can withstand freezing cold and moist conditions, this might just be the ideal stuff for you. It’s affordable too; at less than $200 you get a budget sleeping bag with high fill power.
Weight: 2lb 13oz
Temperature Rating: 15 degree
Shape: mummy style
Insulation: duck down
Cotopaxi Sueno Sleeping Bag is lightweight with a temperature rating of 15 degrees, versatile enough to be used through fall, spring, summer, and mild winter.
It comes in a classic mummy shape and ample foot space. It is made of water-resistant duck down with fill power of 800.
If you’re looking for a sleeping bag that is wide enough to turn over in at night, light enough to carry easily, and can keep you warm and comfortable in most seasons, this is the sleeping bag for you.
Temperature Rating: 15 degree
Shape: mummy style
Insulation: goose down
This sleeping bag a durable, lightweight and affordable four-season rated bag. It has an extreme limit of 15 degrees F and a lower limit of 30 degrees F which makes it suitable for very cold outdoor conditions.
Its insulation is made with goose down with a fill power of 800 and the shell is made of waterproof fabric treated with water repellent.
This is another great budget sleeping bag—well under $200—and it integrates so well with your hammock.
Choosing a can be a compromise between factors like weight and insulation but somewhere in-between you will get the right sleeping bag specifications that meet your needs.
Also, persons who camp around the year may have different sleeping; bags for the harsh winter conditions and for the warmer seasons.
Some Frequently Asked Questions
- What does the temperature rating mean on a sleeping bag?
The temperature rating specified on sleeping bags usually refer to the comfort temperature rating—that is the lowest temperature at which a standard man can sleep comfortably for a night in the bag.
- How do you stay warm in a sleeping bag?
A regular sleeping bag uses multiple layers of special cloth to keep the user warm. Also, special insulation made from duck feather, goose feather or synthetic fiber is locked in between the cloths to prevent you from losing body heat to the cold environment.
- What is the best winter sleeping bag?
The best sleeping bag will be one that provides sufficient warmth and still has a lightweight. For winter, the sleeping bag would be a four-season or five-season sleeping bag with a comfort temperature rating of 10 degrees. Preferably, it should have a duck down insulation with a fill of at least 800 and a water-repellent shell material.