Merino Wool FAQ at a Glance

Why doesn't merino smell?

Firstly, wool is not a hollow fiber where bacteria can easily settle. Secondly, protein molecules and sulfur proteins in the fiber core create an environment where odor-forming germs find it difficult to colonize. You can find more information on the fiber structure of wool and its self-cleaning function in our lexicon article "Why Merino Underwear?"

How fast does merino wool dry?

Merino wool can temporarily store a lot of moisture without feeling wet and uses this moisture for cooling when it's hot. At the same time, the wool keeps the body warm enough even when damp in cooler outdoor temperatures, preventing chilling or shivering.
While synthetic fibers dry faster than wool, they also cause a very high fluid loss from the body and strong evaporative cooling during inactive phases. Therefore, very fast drying is not necessarily advantageous.
Merino wool also feels dry on the body quickly, even if moisture is still buffered in the fiber core.
For people who sweat heavily, a merino blend fabric can still be useful to shorten drying time or to prevent the fabric from becoming too heavy due to wetness.
We wanted to know exactly, so we conducted a self-experiment comparing the drying time of a 100% merino shirt from Icebreaker with a merino-Tencel® shirt from Ortovox:

Video

The test deliberately simulated hand washing and thus a very wet state to assume the "worst case".
Machine washing, of course, results in a much shorter drying time due to spinning. The same applies to drying on the body or in the sun.

Is merino too warm in summer?

There is such a thing as a fiber that can do both – warm and cool at the same time. Wool is associated with winter in many people's minds. Unjustly so, because it is the ultimate all-rounder and unrivaled in this respect. No other material creates a more balanced relationship between warm and cold. This is because water vapor molecules are buffered in the fiber core of merino wool and have a cooling effect when it's hot. At the same time, when the temperature drops, body heat is retained by air pockets in the crimped fiber structure, even if the fabric is still damp. With this principle, wool has been a functioning air conditioner for thousands of years and also the reason why sheep do not overheat on the pasture even in summer. Try it out and trust what nature already demonstrates.

Is merino wool breathable?

Wool, on the other hand, absorbs up to a third of its own weight in water vapor without feeling wet. The moisture is evenly released outwards. The slower evaporation combined with excellent heat retention despite the stored moisture creates a natural regulation of perceived temperature. Wool is therefore breathable in the sense that it prevents overheating and at the same time does not lead to chilling during inactive phases.

How warm is merino wool?

Wool is one of the warmest materials in the world and has therefore been used for clothing for thousands of years. Due to its ultra-fine fiber thickness, merino wool can also be processed into high-performance functional clothing with special heat-retaining structures using modern knitting technology.
When it comes to functional underwear, merino wool is unbeatable in terms of warmth and, at icy outdoor temperatures, far superior to all synthetic fibers, especially due to its heat retention in a damp state.
We offer a wide range of extremely warm underwear that is also ideal for double-digit sub-zero temperatures.

Is merino wool scratchy?

This topic always causes a lot of discussion. Unfortunately, these discussions are often not fact-based, especially by proponents from the synthetic fiber camp, because wool is not just wool.
Even with the noblest form of sheep's wool (merino), there are big differences in fiber fineness (between 14 and 22 microns). The following factors influence the softness of the finished merino fabric:

Country of origin of the merino wool and the climatic conditions there
Rich pastures and animal welfare-friendly farming
Selection of the best wool qualities from the underbelly of the merino sheep (this point is a major cost factor)
Further processing of the wool with know-how and state-of-the-art knitting technology

As with wine, there are even different vintages of this natural product that produce differently soft wool. As a rule of thumb, the greater the temperature differences and the juicier and more biodiverse the meadows, the higher the wool quality. Therefore, our suppliers almost exclusively use merino wool from New Zealand, Tasmania or the South American Andean regions. Animal welfare-friendly sheep farming is also a basic prerequisite for high-quality wool.

Even if scientific studies assume that scratching is no longer perceptible by humans below 20 micron fiber thickness, there are people with very sensitive skin who may still feel a slight tingling sensation. This can also be accompanied by a psychological effect of an expectation. In most cases, it is sufficient to wear a merino shirt for more than 15 minutes until the skin gets used to it.
90% of all users find merino wool very comfortable on the skin. Alternatively, for extremely sensitive skin types, there are numerous products with merino blends that have an even softer wearing comfort and are definitely scratch-free. However, there is one exception: if you have a known animal hair allergy, you should refrain from using it.

Does merino wool have UV protection?

Who thinks of merino shirts first when it comes to UV protective clothing? With a UPF value of 30-50, textiles made from merino wool actually offer exceptionally high UV protection, surpassed only by specially treated UV protective clothing. The thicker the fabric and the denser the weave structure, the higher the UV protection. Most merino shirts (fabric weight of 150-180g/m²) have a UPF of 40 or more. With a UPF of 40+, approximately 97.5% of harmful UV radiation (UV-A and UV-B) is blocked.
For comparison, a white cotton shirt only has a UPF of 10+. The UPF value (=Ultraviolet Protection Factor) indicates, similar to sunscreens, by what factor the skin's natural self-protection can be extended in time.
Many merino sheep live in Australia, where they are exposed to one of the strongest UV radiation levels on the planet. No problem, because wool naturally protects against sunburn and has more sun protection than any other natural fiber.
However, it should be noted that the color of the textile also plays a role. Darker colors provide better protection as they additionally reflect sunlight. If a fabric is wet or stretched, the UV protection may decrease.
In addition, sensitive skin types (e.g., red-haired, light-skinned) should combine UV protective clothing with sunscreen on exposed body parts such as shoulders and neck.
Basically, the natural UV protection of merino clothing is perfectly sufficient for many outdoor activities, and all without skin-damaging additives as in many sunscreens and without chemical treatments and the annoying sweat odor of synthetic fiber clothing.

Does merino wool get burn holes? (Image of socks by a campfire)

While synthetic fibers are literally highly flammable, wool is very difficult to ignite. Wool does not burn, but only chars, and this requires temperatures of over 500° Celsius. A spark is therefore not capable of damaging merino clothing. A cozy campfire is therefore not an issue.
Due to its flame-retardant properties, wool is also used in fire protection clothing or building insulation and meets the highest safety standards.

Does wool generate static electricity?

Wool is generally considered antistatic and is therefore also used as workwear in electrostatically sensitive areas.
Nevertheless, there are always reports that contradict this. This misinterpretation mainly stems from the fact that other fibers (especially synthetic fibers) can become charged by friction on the crimped wool hairs.
For example, if a synthetic fleece jacket is pulled over a merino long-sleeve, it can crackle quite a bit.
Merino wool by itself, however, hardly reacts electrostatically even with friction. If you doubt this, it's best to do a self-test:
Just rub a shirt made of 100% merino wool over your hair for 30 seconds and notice that not much happens. If you like, you can then repeat the same with a synthetic fabric and see how your hair literally stands on end.

How durable is merino wool?

The answer here is "It depends." Experienced manufacturers like Icebreaker, pictured above, regularly subject their fabrics to stress tests and continuously work to improve knitting technology.
The finer and thinner the wool fibers, the less tear-resistant they are. At the same time, precisely these fine qualities are of particular importance because they are the softest.
The well-known merino brands repeatedly prove that it is possible to achieve both.

"I have merino shirts in my closet that date back to the founding of the Merino Store, have been washed hundreds of times, and still don't have holes" (Quote from CEO Andreas Schechner)

Like most natural fibers, wool is not as tear-resistant as synthetic fibers. In a practical comparison of "merino vs. synthetic fiber", this is one of the very few points where synthetic fibers have an advantage. After all, they are made of plastic, which in turn not only comes at a high price for the environment but also has many functional disadvantages compared to merino wool.

Thicker merino fabrics (from 180g/m²) are less prone to tears or holes. For thinner fabrics, especially under higher stress (e.g., from a heavy backpack), it makes sense to either use merino blend fabrics or shirts made with the "Corespun method," where a thin synthetic fiber core is spun with merino wool as a stabilizing base.

In addition, the lifespan of merino functional clothing can be significantly extended by following a few simple rules. You can find more information about this in our Merino care instructions.

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