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Everything about our Lowland Outdoor sleeping bags


Down is a popular insulation material for sleeping bags because of its excellent thermal insulation properties. It consists of tiny fluffy feathers that come from birds. Duck down and goose down are the two most common types of down used for sleeping bags.

An important factor in determining the quality of down is its fill power, which is measured in cubic inches per ounce. This refers to the amount of space the down takes up when compressed. The higher the fill power, the more air the down can hold and the better it insulates.

In general, goose down has a higher fill power than duck down, meaning it holds more air and thus insulates better for the same weight. This makes goose down a better choice for extreme cold conditions or for people looking for very lightweight sleeping bags. However, goose down is also more expensive than duck down.

Duck down can still be of high quality and is usually slightly cheaper than goose down. For most campers and backpackers, duck down will be more than enough to keep them warm and comfortable during their adventures. In fact, a high-quality sleeping bag with duck down can provide comparable performance to one with lower-quality goose down.

In addition to the type of down, it is also important to consider the sleeping bag's fill weight, sleeping bag construction and outer cover. Fill weight refers to the amount of down used in the sleeping bag and affects insulation performance. Good construction, such as rooms with boxy construction and zipper insulation, can also contribute to thermal insulation and comfort. The outer cover must be durable and water-repellent to protect against moisture and condensation.
In short, both types of down are excellent choices for sleeping bag insulation. If you plan to camp in extreme cold conditions or are looking for a very lightweight sleeping bag, goose down may be the better choice. But for most campers and backpackers, duck down will be more than adequate and is often a slightly cheaper option

How warm should the sleeping bag be?
This question is difficult to answer because most active outdoor enthusiasts want a sleeping bag that is suitable for all their activities throughout the year. A sleeping bag that is not too warm in the summer but still nice and warm in the winter, that rolls up small and, of course, weighs nothing. We are also looking for such a sleeping bag! The simple fact is that no sleeping bag is ideal under all conditions. Therefore, choose a sleeping bag that will suffice during the majority of your activities. A 3-season sleeping bag is fine for all-round use. If you occasionally go camping in the winter, the question is whether you should purchase a true 4-season sleeping bag. A 3-season mummy can be upgraded with a fleece liner. For serious winter trips, of course, nothing beats a serious winter sleeping bag. There are lots of factors that determine the difference between a healthy night's sleep and lying awake due to heat or cold: temperature, altitude, wind speed, humidity, state of health, strenuous activity, diet, alcohol(!), etc. This makes the application of temperature classification for sleeping bags dubious at best and misleading at worst. We use a seasonal classification in 4 categories; from 1-season for a summer sleeping bag to 4-season for a winter sleeping bag also suitable for higher altitude. In addition, we offer sleeping bags in the expedition class for the most extreme conditions: polar, high mountains, etc. This classification is not perfect, but in our opinion it is the most useful to indicate the performance of a sleeping bag.

A mummy or blanket model?
There are roughly two models of sleeping bags: mummies and blankets. Mummy models are cut to follow the body shape as much as possible. Mummy models have a contoured hood to prevent heat loss through the head and neck. Because of its efficient insulation, the mummy model is the best choice for any active outdoor athlete who wants the highest insulation value with the least weight and packing volume. Blanket models offer more leg room for movement and can be used as a comforter at home if necessary. But every time you turn in your sleep, you hit a cold spot in the sleeping bag and it takes energy again to warm it up.

Down or synthetic?
Both have their advantages and disadvantages. We will try to break it down as briefly and concisely as possible:

Advantages and disadvantages of down sleeping bags
A sleeping bag can be filled with goose or duck down. The down flake of goose is larger and more resilient than that of a duck. Therefore, a sleeping bag filled with goose down is warmer with equal fill weight and composition. The purity of the down is also important for warmth. Purity is indicated in a percentage. A purity of 85% means: 85% down and 15% feathers. 96% is the highest possible percentage. The purer the down, the higher the insulation value. Our down sleeping bags are filled with the best quality Eastern European duck or goose down. A second measure of the quality of down is the fill power index. This is the expansion/springiness of the down determined using the Lorch test of the IDFL (International Down & Feather Laboratory). The greater the fill power index, the higher the insulation value. Down with fill power index of 700 means that 1 ounce (28.35 grams) of down can expand to 700 cubic inches (11.5 liters). The fill power index of the down types in our sleeping bags is between 480+ and 750+. The Lorch test is considered the standard test. However, we should note that some countries (e.g., the United States) use a different test that gives a higher fill power index for the same down. The average lifespan of a down sleeping bag is 8 to 20 years.

Pros and cons of synthetic sleeping bags
There are many different models of sleeping bags with synthetic filling on the market. Many manufacturers claim to produce a filling that rivals the insulation value and durability of down. None of these claims can hold up in practice. Yet there is one major advantage: a wet synthetic fill dries much faster than down. This makes synthetic sleeping bags an interesting alternative for sailors, cavers and those who need to stay overnight in wet conditions for extended periods of time. The claim that a synthetic sleeping bag still has a high insulation value when wet is a fairy tale. We've tried it!

Filling: down or synthetic?
The advantages of down are that it is lighter and much more compact to pack compared to a synthetic fill, and it lasts longer. Also, a down sleeping bag sleeps more comfortably because you are less likely to feel stuffy in it. It has a wider temperature range. The disadvantage of down is that it is more expensive to purchase than a comparable synthetic sleeping bag. In addition, a down sleeping bag does not dry as quickly as a sleeping bag filled with synthetic material.

The fill power of down determines the insulation value of the sleeping bag. The higher the fill power, the higher the insulation value. This fill power is measured by placing a certain amount of down with a weight on it in a cylinder. The greater the "resilience" of the down, the more air remains between the down feathers and the better the insulation. The higher the fill power, the higher the quality of the down.
The European standardization of fill power uses 30 grams of down and a weight of 94.25 grams. In the test, temperature and humidity are kept constant.Fillpower is expressed in cubic inches per ounce, or CUIN. In the United States, the procedure for determining fillpower is slightly different.It uses a different preparation of down and different weights

If you use your sleeping bag in temperatures well below zero, perspiration can cause ice to form inside the sleeping bag. This happens in both down and synthetic sleeping bags. Lay the sleeping bag to dry in the sun during the day to make the ice disappear. When it is not possible to dry the sleeping bag, down can collapse much more than synthetic material when used for extended periods below freezing.

Lowland Outdoor is against live plucking of ducks or geese
In the EU, live plucking of animals is prohibited. The largest producers of feathers and down are located in Poland, Hungary and China. Many sleeping bags come from the Far East and the origin of the down cannot be traced. Lowland uses only down from dead animals. Suppliers are excluded if it cannot be excluded that the down comes from live plucked animals. Our down is therefore imported with a certificate issued by our supplier from which we can determine that the down comes from a slaughterhouse.

The comfort temperature of sleeping bags
If there is one complaint that is often voiced about sleeping bags, it is that the sleeping bag turns out to be not at all as warm as it actually indicates on the labels. Many people stare blindly at the temperature data given by manufacturers and therefore buy a sleeping bag that is too cold (or sometimes too warm). Should your Lowland Outdoor sleeping bag be too cold, we can refill it to a higher temperature value.

The need for a standard: EN 13537:2002
The above negative views have been a thorn in the side of manufacturers, retailers and consumers alike for years. For A-brand manufacturers, it is frustrating because their sleeping bags are compared to lower quality sleeping bags even though the labels indicate the same temperature range. For retailers, it's difficult because they have to convince a customer that some (for American) brands often present the temperature range as slightly rosier than it actually is. And for consumers, it is simply difficult to know which brands are actually "warmer" or "colder" than the data shown on the labels. So it was time for a standardized test, where data (and thus sleeping bags from different brands) could be compared much better.

What exactly does EN 13537:2002 mean?
The test to which the EN 13537:2002 standard gives its name is based on completely different principles than previous tests. For example, a mannequin (test doll) is tested, which lies in pre-specified clothing in a sleeping bag on a pre-specified sleeping mat. In other words: at what lowest temperature does a normal-sized woman not feel cold in this sleeping bag when lying down? We also look at the lowest temperature at which a normal-sized man is not cold when lying with his legs raised in the sleeping bag (limit temperature). Finally, we look at the extreme temperature at which a normal-sized woman is at risk of frostbite (extreme temperature). It should be noted that EN 13537:2002 is not valid for sleeping bags for military use (the average user and the material are different from those of consumers) or for sleeping bags for extreme conditions (expedition sleeping bags). In addition, the standardization does not only consist of having the test performed, but also imposes strict requirements on how one and other is displayed in sleeping bags for the end user.

Benefits of EN 13537:2002
Because the tests are always conducted in the same way and under the same conditions, the advantage of this standardization will soon be clear: both retailers and consumers can compare the temperature range of sleeping bags much better. Moreover, the chance of buying a sleeping bag that is "too cold" is much lower, because the comfort temperature assumes a woman of normal build and is thus much easier to compare with the average consumer. An additional advantage for manufacturers is that they are in a much stronger position when it comes to claims about temperature range, because the standardization is a European standard that can hardly be disputed.

Disadvantages of EN 13537:2002
There are also disadvantages to the new standard, however. For example, the test is quite expensive and can cost up to 100,000 Euros for manufacturers who carry many models for different seasons. In addition, all labels and catalogs must be provided with the new values. There are also several people in the outdoor sports world who do not agree with the way the test is carried out. This would not take sweating into account, something that actually has a great influence on the wind chill and level of comfort. There are also comments about the clothing used (it is the same during all measurements, while a real person wears less clothing in warmer temperatures than in cold temperatures) and the sleeping mat used (it is thicker than the most common sleeping mats used by outdoor athletes. Those same critics also point to the unrealistic conditions under which the sleeping bags are tested: the test sleeping bag must be rolled out 12 hours in advance, the wind speed must be a maximum of 5m/sec, the humidity is capped (both inside the sleeping bag and outside), etc. All conditions that are often not true in reality (outdoors). Last but not least, the test can only be performed in a few institutes, so there is a waiting period before it can be performed. The result, of course, is that not all manufacturers who requested the tests already have results. By the way, another disadvantage is that it will still prove difficult for people to compare themselves to the "test subject." If someone is cold, he/she will have to take that into account when buying a sleeping bag and thus buy a warmer sleeping bag. Moreover, outdoor conditions are often variable (well fed or not well fed, rested or not, strong wind or no wind) that one is much more sensitive to cold one time than other times. The test subject of the test is obviously not affected by this.

We as Lowland Outdoor are "conservative" in specifying temperatures. We also do not apply the EN 13537:2002 standardization to our sleeping bags. Should a customer still feel too cold, we fill the sleeping bag to the desired comfort temperature.