Down or synthetic fibre?

Lightweight and efficient insulation of down

The advantage of down as an insulator is its warmth-to-weight ratio – it is both lightweight and warm. In other words, a certain amount of down provides more warmth than the same amount of synthetic material, and correspondingly, more synthetic material is needed to achieve the same warmth as a smaller amount of down. Therefore, down is often the go-to choice for extremely cold conditions. Additionally, down compresses into a smaller space than synthetic fibers, which becomes more significant as you move to thicker jackets or sleeping bags. If you want to hike lightly and save space in your backpack, down is often a sensible choice.

Previously, the weakness of down was its reduced insulating ability when wet. However, many manufacturers now treat down to significantly improve its water repellency compared to untreated down.

When choosing down products, it's also important to consider the ethical aspects of down. In recent years, manufacturers have increasingly highlighted animal welfare themes. Down can be produced responsibly as a byproduct of meat production, which also has many points in favor of animal welfare. Certifications like Responsible Down Standard (RDS) and Advanced Global Traceable Down ensure that birds are not live-plucked or force-fed, and their welfare is given special attention.


Moisture-resistant and evolving synthetic materials

The advantage of synthetic insulation is that it does not require special treatments for moisture resistance; synthetic fibers remain lofty even when wet. Therefore, synthetic material is often a better choice for activities in wet weather or for very sweaty activities. Synthetic insulation also does not escape through potential holes as easily as down, which is important to consider if you engage in activities where your clothing is prone to punctures.

Another significant advantage of synthetic insulation is the price: synthetic-filled jackets or sleeping bags are often more affordable than their down counterparts. This is also worth considering in your purchasing decision.

Although synthetic fibers do not match the warmth-to-weight ratio of natural down, technological advancements in this area are rapid, and new innovations are constantly being made. Many manufacturers' synthetic fills are already quite successfully approaching the properties of down in terms of lightness, compressibility, and insulation.

For vegans, it's worth noting that synthetic fills offer excellent vegan alternatives. For example, the Polartec and Primaloft products we sell are entirely vegan in terms of their fill.

There is variation within both insulation materials

Down comes in different qualities, measured by a specific cuin or fill power value. Generally, a value exceeding 600 indicates high-quality fill. The higher the value, the better the insulation capacity of the down relative to its volume.

There are also differences in synthetic fibers that affect the product's weight, compressibility, and insulation. For example, lower-quality fiber may flatten over time and not return to its lofty and insulating state. Therefore, it's worth investing in high-quality synthetic fill.

Other insulation materials

Entirely new insulation solutions are constantly being developed, and they form an interesting niche. We have already seen wool fiber fill and innovations based on nettle inside jackets. The cellulose fiber industry is advancing rapidly. However, as far as we know, there is not yet a mass-produced new-age fill made from renewable natural materials on the market. The problem with these tends to be that although good fills have been created, they do not compete in terms of lightness, compressibility, insulation, and moisture resistance with the long-developed fills currently on the market. However, the development of new natural fiber fills is an intriguing field that we at Varuste.net are closely following with great interest.


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