Sleeping Under the Stars: How to Choose the Best Sleeping Bag for Your Camping
Spring is coming. Let’s go camping and mountain climbing. Is your sleeping bag suitable? Do you need to buy a new one? Thus, the dilemma arises again.
Some people don’t know what sleeping bag to buy, or more precisely, they don’t know which type of sleeping bag is suitable for the environment they will face. In the end, they hastily make a purchase after only roughly understanding temperature ratings and comparing prices.
There are also some people who consider factors such as fill power and loft when purchasing a sleeping bag but overlook other crucial factors that determine whether a sleeping bag is good or not.
Indeed, a suitable sleeping bag is a balance between an acceptable price and a design that is suitable for the intended environment. However, the latter is particularly complex and cannot be measured by the above indicators alone. This is also the focus of this article.
It is not easy to purchase a sleeping bag that is suitable for the environment one will face.
However, even the widely known indicator of ‘temperature rating’ may not be fully understood by many outdoor enthusiasts.
Sleeping Bag Temperature Rating
As a life-saving equipment that maintains body temperature, how ‘warm’ a sleeping bag needs to be to resist the environment you will face? This involves the first question you need to face when choosing a sleeping bag: temperature rating. It is not simply a temperature label provided by the manufacturer, nor is it an absolute standard to determine whether a sleeping bag is suitable or not.
The EN13537 standard (now updated to ISO 23537-1:2016) – outdoor enthusiasts who purchase international brand sleeping bags should have noticed this rating standard. This standard was introduced by the European Standardization Committee and requires all sleeping bags sold in Europe after 2005 to comply with it. It has since been adopted by many international brands.
Temperature scale display for an EN rated sleeping bag
Regarding the temperature measurement section, this standard involves inserting a human model that is fitted with sensors and wearing inner clothing into a sleeping bag for testing. The model is preset as a “standard male” with a height of 1.73 meters and a weight of 73 kilograms at the age of 25, or a “standard female” with a height of 1.6 meters and a weight of 60 kilograms at the age of 25. This test will produce four results:
Upcoming EN13537 temperature standard test for sleeping bags
- Comfort Temperature: The lowest ambient temperature at which a standard female can comfortably fall asleep in a relaxed position inside the sleeping bag without feeling cold.
- Lower Limit Temperature/Limit Temperature: The lowest ambient temperature at which a standard male can curl up inside the sleeping bag without feeling cold.
- Extreme Temperature: The lowest ambient temperature at which a standard female can curl up inside the sleeping bag for 6 hours without experiencing hypothermia but may shiver.
- Upper Limit Temperature: The highest ambient temperature at which a standard male can have his head and arms outside the sleeping bag without sweating.
There may be differences between the EN temperature ratings and actual experiences – while the EN temperature rating provides a reliable and uniform standard, the real environment is different from the testing environment, and many variables such as personal physique, sleepwear, diet on that day, sleeping pad R-value, etc., can affect your actual perception. The latest version (ISO 23537) also notes that this standard may be inaccurate in extreme climates below -20℃.
The true temperature required may differ from the sleeping bag temperature label
There are still many sleeping bags without the EN temperature rating – many mountaineering enthusiasts buy sleeping bags that have not been tested and only have the temperature rating suggested by the manufacturer. For such sleeping bags, you can use the manufacturer’s suggested temperature rating along with other parameters to make a judgment.
Summary: Temperature ratings are just a reference – so when purchasing a sleeping bag, the temperature rating is only an auxiliary reference for you. It is also important to pay attention to others’ reviews, and to leave extra margin in case of extreme cold weather.
The comfort temperature in the temperature rating is the most important reference for you when selecting a sleeping bag, and you should avoid being in the extreme temperature range indicated on the sleeping bag. For example, in the winter mountain areas in the north, the temperature inside the tent may drop to -15℃, so you should choose a sleeping bag with a comfort temperature of -20℃.
After determining the temperature rating, you also need to consider many other factors, such as the filling inside the sleeping bag. Especially for sleeping bags without EN certification, you can compare them with EN certified sleeping bags with similar filling to further determine their warmth.
Sleeping bag fill: Synthetic cotton or down, duck down or goose down?
Synthetic cotton and down
The warmth of a sleeping bag largely depends on the filling material in the fabric, which is the “inner part” of the sleeping bag. Mountaineers mainly choose between synthetic cotton and down, and down sleeping bags can be further divided into duck down and goose down. Which filling material can meet your needs?
Low price, lightweight, warm, easy to compress, durable, water-resistant, quick-drying, and able to keep warm even in damp conditions… this is certainly the ideal filling material, but unfortunately, you cannot have it all, and can only focus on selecting according to your needs.
Synthetic cotton vs. down – “cheap, bulky, easy to get wet,” many mountaineers have such impressions of cotton sleeping bags. In fact, synthetic cotton is essentially a kind of synthetic fiber, with many different types and varying quality, such as Primaloft cotton, which has better compression resistance and is therefore used in some sleeping bags for the back and hip areas. Some merchants claim that synthetic cotton has the advantage of keeping warm even when wet.
Overall, compared to down sleeping bags, synthetic cotton has a shorter lifespan, is difficult to compress, and has poorer thermal performance. Therefore, the mainstream choice for mountaineers is still down sleeping bags.
This leads to a new question: What kind of down sleeping bag is better?
Duck down vs. goose down – many mountaineers believe that goose down is more high-end and a standard feature of high-end sleeping bags, with prices generally higher than duck down sleeping bags. The reason is:
- Goose down has larger down clusters, longer fibers, smaller and more evenly distributed fiber branch nodes, and better resilience, thus providing better loft and capturing and trapping more air, making it more warm.
- Goose down also has a milder and cleaner odor than duck down because geese are only herbivores, while ducks are omnivores. As a result, goose down has a lower oil content and less odor.
- Ducks have a shorter breeding cycle and higher down yield, while geese have higher breeding costs and lower down yield.
However, the statement that “goose down is warmer than duck down” is not absolute. Different varieties, feeding time, feeding management mode, hair collecting season and method, processing technology, etc. can all cause differences in the results (even to the extent that it is difficult to distinguish between duck down and goose down). For example, the density of feather fibers in ducks raised in high-altitude areas can rival high-quality goose down, and there are also expensive high-loft duck down sleeping bags on the market.
As for the odor issue, the requirements for cleanliness, odor, and residual fat rate of duck down and goose down are the same. Duck and goose down that has been properly washed should be clean, disinfected, and odorless (or only have a slight odor). Down with strong odors is likely to not meet the standards.
Summary – When it comes to filling material, down is the best choice for outdoor enthusiasts (synthetic cotton can be used as auxiliary filling material). After determining the temperature rating, you need to choose between duck down and goose down: except for a few top-quality duck down sleeping bags, most duck down sleeping bags have better value for money, while goose down sleeping bags are better in terms of loftiness but more expensive.
Checking the loftiness is also the third step in choosing a sleeping bag, and you should also look at the filling weight and down content, which are important performance indicators for down.
How to determine the fill power, down content, and loft of a sleeping bag?
If you carefully read the sleeping bag instructions, you may see descriptions such as “400g fill weight,” “90% fill power,” or “90/10 white duck down,” “700+ loft,” which refer to the fill weight, fill power, and loft of the sleeping bag. What is the value of these values in helping you choose a sleeping bag?
Fill power refers to the weight of down filling in a sleeping bag, such as a 1300-gram duck down sleeping bag or a 400-gram goose down sleeping bag. With the same filling material, the higher the fill power, the better the insulation (although the fill power cannot be too high, otherwise the down will compress each other and squeeze out the trapped air, which is not conducive to warmth).
Of course, the higher the fill power, the heavier the down sleeping bag will be.
Fleece content refers to the percentage of down clusters in the total weight of the filling material in a down sleeping bag. Down is composed of quills and clusters, with the clusters being the part that provides insulation. The down clusters can be classified into various types based on their shape, including tufted down, immature down, similar down, and different-colored down, but not including down fibers. However, in some standards, the percentage of both down clusters and fibers in the filling material is considered as the down content, which may be misleading as low-quality down fibers can increase the percentage of down content while reducing the overall quality and performance of the down.
The higher the down content, the better the loft of the down, but some studies have also shown that when the down content exceeds 75%, the change in the loft of the down is not significant, so there is no need to pursue the ultimate loft.
Loftiness – refers to the volume of down that can be restored after being compressed. The higher the loftiness, the more insulating air trapped in the down, and therefore, the better the insulating performance.
Same weight, different fluffiness of down
The loftiness of down refers to the volume that can be recovered after compression. The higher the loftiness, the more insulating air the down contains, thus providing better insulation.
During testing, the error in loftiness measurement is smaller compared to other indicators, making it easier to control, and closely related to the warmth of the sleeping bag. Therefore, loftiness can be regarded as a key indicator of the quality of down.
There are many standards for measuring loftiness, and businesses typically use the USA2000 standard. For example, the commonly seen “650+ loftiness” indicates that one ounce of compressed down will recover to 650 cubic inches or more. Popular brand sleeping bags generally achieve this value, while high-quality sleeping bags can reach 850+.
Summary: Based on the three performance indicators of down sleeping bags mentioned above, loft and fill power should be the main focus. If you want to choose a sleeping bag for a certain temperature range, you can consider the cost-effectiveness: high fill power but average down percentage and loft, which will make the sleeping bag heavier; or you can choose a lightweight and comfortable option with lower fill power but excellent down percentage and loft.
It’s worth noting that as the “stuffing” of a sleeping bag, the quality of down is not visible and may not be discernible by touch. Therefore, for safety reasons, it’s best to buy a sleeping bag with a brand guarantee. Manufacturers will also try to maintain the quality of down to protect their own brand and will usually have their down tested by organizations such as the International Down and Feather Laboratory (IDFL).
If you want to choose a sleeping bag of top-notch quality, you should pay attention not only to the aforementioned factors but also to the filling structure, which is a significant factor for coping with extremely cold environments.
Sleeping bag waterproof
In complex environments such as snowy mountains, mountaineers entering and exiting tents will bring in snow. Cooking and boiling water inside the tent may result in water spills, and condensation can cause sleeping bags to become damp. Down sleeping bags are particularly prone to absorbing water, and lose their insulating properties when damp. How do sleeping bag manufacturers deal with this?
Water-repellent down – the down is treated with a water-repellent treatment, such as some brands labeled as ULTRA-DRY Down. This is a hydrophobic polymer treatment that can protect the down from the effects of water vapor and condensation.
On the left is water-repellent treated down, on the right is regular down. Both were put in a water bottle and shaken for two minutes. The down on the left still retains a considerable amount of fluffiness, while the down on the right has almost lost its functionality.
Water-resistant fabrics – Nylon is currently the mainstay fabric for sleeping bags, and in addition to preventing down leakage, manufacturers also apply water-resistant treatment to prevent water droplets from penetrating. This can increase the sleeping bag’s ability to resist moisture. Some sleeping bags even use waterproof eVent fabrics, which may be considered by mountaineers with high waterproof requirements.
In rainy or snowy environments, staying in the tent to eat and drink makes the waterproof performance of the sleeping bag important.
Sleeping Bag Shape and Size
On the left is a women’s sleeping bag, and on the right is a unisex sleeping bag.
Rectangular sleeping bags are roomier and more comfortable, while mummy bags are more thermally efficient.
The mummy-style sleeping bag, which gradually narrows from the shoulders to the feet and follows the curve of the human body, is the mainstream choice for mountaineers. Manufacturers set various specifications for sleeping bags, but you can also customize them yourself. A well-fitting sleeping bag (slightly longer than your height and slightly wider than your body) can keep warm air close to your body and effectively insulate you. If it’s too tight, it will be uncomfortable, and if it’s too big, some parts will be colder.
To address the fact that women feel colder and have different body types than men, some sleeping bag brands have introduced women’s sleeping bags that are wider in the hips, narrower in the shoulders, and have added down in the torso, feet, and other areas, as well as using lightweight fabrics.
Some high-altitude sleeping bags have larger foot spaces, making it easier for you to wear down foot covers and stuff clothes inside, ensuring warmth for your feet.
Sleeping Bag Weight
The weight of outdoor sleeping bags can vary greatly depending on the size, materials, and temperature rating. Some ultralight sleeping bags can weigh as little as a pound (450 grams), while heavier winter sleeping bags can weigh up to 6 or 7 pounds (2.7-3.2 kilograms) or more. Generally, a typical backpacking sleeping bag can weigh between 2 to 4 pounds (0.9-1.8 kilograms). It’s important to consider the weight of the sleeping bag when planning your backpacking trip or outdoor adventure, as it can significantly affect your overall pack weight and comfort level while carrying the gear.
Ultra-lightweight fabric – In order to further reduce the weight of the sleeping bag and meet the demand for ultra-lightweight gear, some manufacturers use high-quality, low-denier (a parameter closely related to the thickness and weight of the fabric) nylon to make the sleeping bag fabric lightweight yet durable. This is a favorite among mountaineers who pursue ultra-lightweight gear.
Sleeping Bag Zippers
You definitely don’t want to suffer from the trouble of getting your zipper stuck or broken on a cold night, so the quality of the zipper is important. A zipper that can flow in both directions can also facilitate your entry and exit as well as temperature adjustment, so you can pay attention to this when making a purchase.
Draft Collar of Sleeping Bag
Outdoor sleeping bag’s draft collar is a feature designed to minimize heat loss and keep you warmer during cold nights. It is a insulated tube that wraps around your neck and prevents warm air from escaping the bag through the opening around your head.
A draft collar typically consists of an internal layer of soft, warm material, such as down or synthetic insulation, and an external layer of water-resistant or waterproof fabric. The collar is often adjustable, allowing you to tighten or loosen it around your neck as needed for optimal warmth and comfort.
The draft collar is a key feature to look for when purchasing an outdoor sleeping bag, especially if you plan to use it in cold or windy conditions. It can help you stay warm and comfortable throughout the night, allowing you to get a good night’s sleep and wake up feeling rested and refreshed.
Sleeping Bag's Hood
An outdoor sleeping bag’s hood is a feature designed to provide additional insulation and warmth around the head and neck area. It is typically a contoured section of the sleeping bag that can be cinched down using a drawstring to create a snug fit around the face.
The hood of a sleeping bag is important because a significant amount of heat can be lost through the head and neck. By providing extra insulation in this area, the hood can help to keep you warmer and more comfortable while sleeping outdoors in colder temperatures.
Some hoods may also feature a balaclava-style design that covers the entire head, leaving only the face exposed. This can provide even greater insulation and protection from the elements.
When choosing an outdoor sleeping bag, consider the type of hood that will be most comfortable for you. Look for a hood that can be easily adjusted to fit your head and neck, and that provides adequate insulation for the conditions you will be camping in.
Sleeping Bag Pocket
Some sleeping bags designed for high-altitude environments may also have a humanized design: a small storage compartment is built inside the sleeping bag to facilitate the storage of electronic devices such as mobile phones, and to prevent them from malfunctioning due to extreme cold.
Sleeping Bag Footbox
The footbox of an outdoor sleeping bag refers to the bottom portion of the bag that is designed to provide extra insulation and warmth to your feet.
The footbox is usually tapered and shaped like a box to provide extra space for your feet to move around and allow for a more comfortable sleeping experience. Some sleeping bags have a more roomy footbox area, while others have a snugger fit for added warmth.
Sleeping Bag Liner
A removable liner sleeping bag is a type of sleeping bag that comes with a detachable liner that can be easily removed and washed. The liner is typically made of a lightweight, breathable material such as cotton or polyester and is designed to keep the sleeping bag clean and fresh while providing an extra layer of warmth.
The main advantage of a removable liner sleeping bag is that it is easy to keep clean, as you can simply remove the liner and wash it separately from the rest of the sleeping bag. This is particularly useful if you plan on using the sleeping bag frequently, as it can help to reduce odors and keep the sleeping bag fresh and hygienic.
Another advantage of a removable liner sleeping bag is that it provides flexibility in terms of temperature regulation. If you are camping in warmer conditions, you can remove the liner to reduce the insulation and stay cooler, while in colder conditions, you can keep the liner in place for added warmth.
Price of Sleeping Bag
Basic sleeping bags can start at around $20-30, while high-end sleeping bags can cost several hundred dollars or more. The price can also depend on the type of insulation used, with down sleeping bags typically being more expensive than synthetic options.
Other features such as the shape of the bag, temperature rating, and special technologies can also affect the price. For example, a mummy-shaped sleeping bag with a lower temperature rating and advanced insulation technology may be more expensive than a rectangular-shaped bag with a higher temperature rating and basic insulation.
Ultimately, the price of a sleeping bag will depend on your personal needs, preferences, and budget. It is important to consider factors such as warmth, weight, packability, and durability when choosing a sleeping bag, and to invest in a quality bag that will provide comfort and safety during outdoor activities.
We have used TETON sports double sleeping bag for over 3 years. It gave us a great outdoor camping experience, keeping our bodies warm in cold weather while still having enough interior space for 2 people.
Care for Sleeping Bag
You should make sure to follow the manufacturer’s instructions for proper care and maintenance of the sleeping bag.
Reviews of Sleeping bag
Read reviews from other customers to get an idea of the quality and performance of the sleeping bag.
We bought this double sleeping bag for 3 years. Many people think this sleeping bag be the best sleeping bag on Amazon. It gets over 5 thousands reviews.
Humanitarian Certification of Sleeping Bag
Humanitarian Certification – Collecting down feathers can potentially be cruel to animals. The Responsible Down Standard (RDS) is a humane and responsible down standard certification that evaluates the animal rearing and handling practices in a manufacturer’s supply chain through third-party assessments to ensure that the collection of down feathers does not cause physical or mental suffering to animals. Sleeping bag brands that have obtained this certification will indicate this.
So, how should we choose a sleeping bag?
Above is our 3 year old double sleeping bag, which can be used for both car travel and outdoor camping. We highly recommend it for families who need a double sleeping bag.
IT has over 4.7 points and get over 5 thousand reviews on Amazon. You can get more details here about this sleeping bag.
Whether a sleeping bag is suitable or not cannot be determined by just a few simple indicators. A high-quality sleeping bag undergoes precise control in both material and design. When choosing a sleeping bag that suits your needs, you can start from the following aspects:
- Check the temperature rating, but even for sleeping bags certified by the EN temperature rating system, it is best to pay attention to the results of real-life testing;
- Choose the filling material – duck down and goose down are mainstream, and except for top-level duck down sleeping bags, general duck down sleeping bags have better cost performance, while goose down sleeping bags have higher loftiness;
- Of the three performance indicators for down sleeping mats, fill power and loftiness are the key factors to consider. Those with official certification from organizations such as IDFL are more trustworthy;
- For dealing with extremely cold environments, sleeping bags with standing lining structures and combination compartmentalized systems are more reliable in terms of warmth and will also be more lightweight;
- For snowy environments, it is necessary to have waterproof down and splash-proof fabrics;
- Other details of the sleeping bag, such as size, zippers, storage compartment design, and humane certification.