Sleeping bag: down or synthetic?
The importance of your sleeping bag's 'power cord
Fill power is the most important criterion to consider when choosing your sleeping bag. It represents the insulation, compression and quality value of your down. The higher the fill power, the higher the quality of the down, ensuring that you will spend the coldest nights warm.
The temperature to weight ratio :
Every hiker wants to maximise warmth while minimising the weight of their sleeping bag. The quality of the down accounts for 70% of the possible weight reduction of a sleeping bag. Therefore, it is important to understand the value of fill power and to compare it when buying a sleeping bag.
It's simple, the higher the fill power, the higher the temperature to weight ratio.
Here is an example:
Compression to weight ratio:
As hikers, we also want our sleeping bag to take up as little space as possible in our backpack. The higher the fill power, the greater the compression of the feather. In other words, a higher fill power will ensure that your sleeping bag takes up less space in your hiking bag. X
The price :
Since the quality of the down is directly related to the value of the fill power, it influences its price.
Down treatment :
In order to increase moisture resistance, many companies treat their down. This treatment (water resistant) increases the swelling factor of the down.
Applying a treatment to the down increases the warmth of the down during the coldest and wettest nights.
The outdoor industry :
We can map the outdoor industry into three categories: low quality companies, large companies and specialised companies.
Low quality companies :
You will find very low and poor quality fill power. These companies set low and attractive prices. The sleeping bags they sell are cheap. However, you will feel the cold on cool nights. The volume of the sleeping bags is also very important.
Large companies :
You will find a fill power from medium (700 fill power) to high (850 fill power). These sleeping bags are suitable for hikes lasting a few days. Sleeping bags are often heavy and take up a lot of space in the backpack.
Specialised companies:
You will find a higher and better quality fill power (above 850). Some companies offer custom-made sleeping bags. Here you can choose the materials, the fill power of your down and other additional features.
Sleeping bags from specialised companies are mainly aimed at hikers who want to go on multi-day hikes and where weight is a determining factor.
Can we trust the temperature value on the sleeping bags?
Yes and no. Always do your own calculations! There are no "standards" for rating sleeping bags. Each company can specify the degree in Celsius or Fahrenheit that it wants. The "quality" outdoor industry is moving towards a standardisation of these values. However, we find many companies on the market that quote comfort temperatures that make no sense and are unrealistic.
How can you compare sleeping bags if the values vary from company to company?
In order to compare two sleeping bags, you need to look at the weight of the down, the fill power and the advertised temperature. With a rule of 3, you can compare the products on the market.
CONCLUSION
The fill power is the most important criterion when choosing a sleeping bag.
In order to compare two sleeping bags, you need to look at this factor as well as the weight of down in the product.
Mathieu Jourjon
Adventurer and Economist
