Guidebook: You must pay attention to this when buying a sleeping bag

The current weather forecast announces a strong stream of breeze that leads ice-cold continental air to the north of the Alps. If you do not want to give up the night in the VW bus or on the crash pad despite the cold, you should choose the right sleeping bag. Andrea Brändli from Bächli Bergsport shows you what you should pay attention to when buying.

A contribution by Andrea Brändli - Bächli mountain sports

What could be better than coming back to the rock after a day, cuddling tired and exhausted in his sleeping bag, reviewing the experience and then falling asleep relaxed? Nobody likes to wake up feeling freezing or sweaty during the night. For this reason, the thermal performance of a sleeping bag is one of the most important criteria when buying. It makes sense to inquire about the different models and fillings and to get advice before buying.

From ultralight to expedition-ready

Sleeping bags can be roughly divided into five areas of use. The categories range from models that are suitable for temperatures around -40 Grad Celcius to models that can be used with their packing size for temperatures up to 5 Grad Celcius.

  1. Ultralight sleeping bag with small packing size up to max. + 5 ° C
  2. Lightweight sleeping bag for trekking from spring to autumn and for summer alpinism up to max. -5 ° C
  3. All-season sleeping bag for trekking, 3 seasonal sleeping bag for high mountains up to max. -10 ° C
  4. Winter sleeping bag for high mountains and expeditions up to max. -25 ° C
  5. Expedition sleeping bag for the coldest regions up to max. -40 ° C

So think carefully about what temperatures and in which season you need your sleeping bag the most. Important is also the following point:

Frozen or cold-resistant - we are all different

Everybody feels temperature differently. This should always be considered when selling. First and foremost, gender is important. Women have a very different need for warmth than men and usually need a warmer sleeping bag. Equally important is whether you go to bed in the evening, rested or exhausted, how much you ate, whether you drank alcohol or how much you move in your sleep. The location of the camp (wind exposure, altitude, humidity, etc.) as well as the insulating power of the sleeping mat also play an important role. Therefore: Also take into account when making the purchase decision.

Care - less is more

The fillings, regardless of whether they are down or synthetic fibers, suffer from every wash. With every wash, the down loses part of its natural fat content, which means that it becomes brittle, breaks and loses its bulk and insulation properties. Synthetic fibers have a rough surface and the fibers are siliconized so that they do not get caught in one another. Every wash puts a strain on the silicone layer and in the long term reduces the bulk of the nonwoven. Therefore: Ventilate sleeping bags in the air and rub out individual stains in the outer material with clear water. Avoid complete washing - as far as possible!

Direct comparison of different brands thanks to EU standard

The European standard EN 2005 has been in force since 13537 for the labeling of sleeping bags, which specifies how sleeping bags must be tested and assessed. The standard applies to all sleeping bags, with the exception of military sleeping bags and models for extreme temperatures (comfort temperature below -25 ° C). In extremely cold temperatures, the clothing and sleeping mat used are different from the norm. Down suits in sleeping bags or military clothing are mostly used there.

So sleeping bags are subjected to the standard test

The EN methodology defines temperature ranges that can be relied on and through which a direct comparison with the EN ratings of other brands is possible. For temperature tests according to EN 13537, a life-size doll ("normal man" and "normal woman" middle-aged, medium-sized and medium-weight) is equipped with heating elements and temperature sensors as well as long underwear and a hat. Then the doll comes in the sleeping bag. The sleeping bag lies on a sleeping mat in a climate-controlled room. The doll is warmed up to human body temperature. Both the temperature of the air in the climatic chamber and that on the doll's “skin” are measured. The thermal insulation of the sleeping bag is determined based on these measurements. The results are decisive for four EN temperature ranges. Only a sleeping bag that complies 100% with the requirements of EN 13537 may bear the CE mark on the product or hangtag.

The four temperature ranges of the EU standard

Temperature ranges-the-EU standard

Upper limit (red, + 25 ° degree): A temperature at which the normal man can sleep without excessive sweating. This area is determined without the sleeping bag hood and with the zipper open.

Comfort (red / yellow, + 2 ° degree): The norm-woman can sleep comfortably in a relaxed position.

Limit (yellow / blue, -5 ° degree)The Standard Man can sleep in a rolled position for eight hours without waking up and freezing because of the cold.

Extreme (blue, -13 ° degree): Survival range, the minimum temperature at which the standard woman can stand for six hours without the risk of death due to hypothermia (with frostbite on the skin not excluded).

Down versus synthetic sleeping bag

Sleeping bags are divided into down and synthetic models. High-quality down insulates much better than synthetic filling materials with the same fill weight, since the fine down traps warm air better than any synthetic fiber. In addition, down sleeping bags are lighter and more compressible. But they are also more expensive than comparable synthetic sleeping bags. Down sleeping bags are particularly suitable for use in the mountains, in our latitudes.
Synthetic sleeping bags, on the other hand, are particularly suitable for areas with very high humidity or for situations in which moisture can be expected for another reason. When wet, the synthetic fibers retain their insulating properties better than down. The new high-quality synthetic fibers have been specially developed for better compressibility, but they do not yet come up to high-quality down models in this regard.

The down sleeping bags in the range of Bächli Bergsport

Sleeping Bag Down Mountain Equipment_Baechli Mountain Sports

The synthetic sleeping bags in the range of Bächli Bergsport

Sleeping bag Synthetic Marmot_Baechli Mountain sports

Down is not all down

A good down sleeping bag is determined primarily by the quality of the down filling. The following factors are decisive: best raw down comes from full-grown and well-kept geese from cold areas. Plucking is done by hand on the dead animal. Only through proper washing and accurate sorting can good fillings be achieved. Since pure down is hardly available and a certain amount of spring is necessary to support the filling, the ratio between down and feathers is given for fillings. A value of 90 / 10 means that the fill is composed of 90 percent down and 10 percent springs. Since feathers have better insulation and lower weight than feathers, best fillings consist of up to 96 percent down. Values ​​of 90 / 10 are still very good.

The Cuin value indicates the insulation performance of the down

But how can the insulation performance of a certain down quality be measured? The more "still" air the filling can store, the better the insulation. Thus, a certain amount of filling must reach as large a volume as possible in order to store as much air as possible in it. A good sleeping bag is thus characterized by the fact that its filling can expand as quickly and voluminously as possible after it has been unpacked. This expansion force after compression is called Fill Power (or Loft, or Bauschkraft) and can be measured with a standardized method. One ounce (28g) of a down fill is filled into a graduated cylinder and loaded with a 24g heavy plate during 100 hours. The plate is then removed and measured to what volume the filling has swelled. The measured volume is given in Cuin (1 Cubic Inch = 16.39 cm³). Good down has a value of over 500 Cuin. 700 to 800 Cuin are top values ​​and can not be surpassed by the international measurement standard.

The chambers optimally distribute the down

In order to achieve the optimum heat output, the downs must be divided into chambers. The various constructions have the task to optimally distribute the down and minimize cold spots. This chamber system exists.

longitudinal chambers


Longitudinal chambers have vertical webs and support a fast and even heat distribution. The chambers run continuously, so that the down can be individually positioned by shaking the sleeping bag.

transverse chambers


Cross chambers have staggered seams. The down wanders into smaller chambers, so-called transverse or oblique chambers, where they are stably positioned. As a result, cold spots can also be prevented on the sides of the sleeping bag, even on the side of the sleeping bag, which in turn ensures maximum insulation.



The structure of the V-chambers is very complex and expensive, but fixes the filling very well and is suitable for extreme temperature ranges. The down is best adhered to the inclined chamber walls. The crossbars are sewn to the side bar, this is in turn mounted between the top and bottom. This prevents slippage of the down.

trapezoidal chamber


The trapezoidal chamber design combines the advantages of transverse and V-chambers, also fixes the filling very well and ensures a uniform down distribution. The best way to stick the down, as in the V-chamber design, on the inclined chamber walls.

Light and tight, or rather ultra comfortable?

More important or at least as important as the chamber system is the shape of the sleeping bag. The following options are available for selection.

Mummy shape - Mountain Fit


With this form of sleeping bag, the insulation is most efficient, as very little heat is lost due to the tight fit. Disadvantage: The freedom of movement is limited. This form is ideal for making extremely lightweight, packable sleeping bags for alpine use.

Mummy shape - Comfort Fit


With the slightly more comfortable version of the mummy sleeping bag you can enjoy more freedom of movement. Nevertheless, this sleeping bag meets the highest requirements, as it is much better insulated than a rectangular sleeping bag.

Rectangular form


This form offers plenty of freedom of movement and is very comfortable. Many sleeping bags with this shape are equipped with an all-round zipper and can therefore be used as a blanket. This form of sleeping bag is by far not as thermo-efficient as mummy sleeping bags and is especially used at not so low temperatures.

Huge selection of sleeping bags for all uses

Im Online Store or in the Branches of Bächli Bergsport You are sure to find the right sleeping bag for a next adventure.

Mountain Equipment_Biwak_Schlafsasck
Here is worth a warm sleeping bag (Picture: Mountain Equipment)



About Bächli mountain sports

Bächli mountain sports is the leading Swiss specialist shop for climbing, mountaineering, expeditions, hiking, ski touring and snowshoeing. Currently offering 11 locations in Switzerland Bächli mountain sports its clientele expert advice and superior service. At LACRUX, Bächli Bergsport regularly publishes exciting articles on climbing and bouldering.



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