Why Merino Wool Keeps You Toasty: The Magical Fiber That Conquers The Cold

Merino wool's soft, breathable fibers trap heat close to your skin, whisking away sweat. Learn why this wool makes the ultimate cold weather adventure clothing.

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Josh Koop

I live with my wife and daughter in Katy, Texas and my local trail is the Lone Star Hiking Trail which is an amazing way to experience the Sam Houston National Park!

Merino sheep grazing in the fields of New Zealand
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I recently wanted to buy some woolen garments as I planned to go on winter hiking trips. After detailed research on different fabric options.

I finally chose to wear Merino wool which would help to keep me warm and dry, even in extreme weather. Which made me wonder, why is merino wool warm?

Hikers should choose Merino wool clothing because of its soft consistency, its ability to absorb sweat, its non-itchiness to the skin, and its freedom from sweaty odors. This material keeps hikers warm and safe around campfires. They will enjoy this lightweight fabric sourced naturally and environment-friendly.

In the rest of this blog post, we will explore what is so special about Merino wool clothing. What makes wool garments made from this type of wool a very good buy even though they can be pricey?

We will see more reasons to use Merino, from wool shirts to socks and everything in between.

The Many Benefits of Merino Wool Clothing For Hikers

The benefits of this are outstanding within activewear, made from this merino wool fiber material:

  • Next to the skin comfort as a base layer, thermal underwear made of this material is not itchy, contrary to one’s preconceived notions.
  • The wool is so soft in texture and is stretchable enough so the garment can be expanded or stretched. It has the ability to return back to its original size and shape upon release.
  • For more comfort, the material is also odor-free because it contains wool wax that kills any odor-causing bacteria. This is quite unlike clothing articles like underwear, shirts, and other hiking accessories made from cotton or synthetic material.
  • The material feels softer on the skin and also lighter than other fabrics & materials
  • Feels warmer than other types of wool with a heavier or thicker consistency.
  • The consistency of the material is fine rather than coarse
  • The clothes made from this wool are safe around fires and also static-free.
  • The material sucks up the sweat from your skin and brings it to the top layer to facilitate moisture evaporation. This process is called moisture-wicking. Wicking helps to regulate temperature during strenuous physical activity or in warmer climates. One’s skin can breathe more easily through this material.
  • Warmer in harshly cold climates as it traps body heat between its fibers
  • Socks made of Merino wool are generally more durable as compared to standard shirts and pullovers.
  • Merino Sheep, are well able to live in warmer summer temperatures with a good amount of wool on their bodies as they possibly have in winter until they are shorn. This is possible because Merino wool has a cooling property. All that moisture or sweat next to their skin is passed on to their outer coat and this cools the air around the animal. A thin merino layer is quite cooling for a warm summer day’s hike.
  • The fiber is entirely biodegradable, natural, and also renewable.

While considering the above benefits of Merino wool fabric it may be wise to avoid some other materials out there in the market during long-distance hiking.

This, not only includes cotton but also denim, corduroy, or flannel that are a strict no-no.

Unlike Merino wool fabric, these don’t provide you any insulation once they are wet because they very quickly absorb water and also take a long time to dry.

This is also something that happens with silk.

The Science Behind Merino Wool’s Unbeatable Warmth

Merino wool is amazing for its many benefits to anyone who lives outdoors for a long time, not just hikers, so why is Merino wool warmer than other clothes?

Merino wool fabric itself is full of a natural loft, the warm air gets trapped in this lofted space allowing the heat to be held inside even when the fabric is thoroughly wetted. Merino wool is also known for being very lightweight and anti-microbial leading to less hiker stank.

Let’s take a deeper look into many other benefits that Merino Wool will give you that will broaden why it is worth the little extra expenditure over other synthetics.

A Deep Dive Into Merino Wool’s Special Properties

We will explore the benefits of Merino Wool in more detail. We will then understand what is so special about Merino wool clothing and the all-around benefits for hikers if they should choose clothes made from this fiber.

The Breathability of the material

The fiber of Merino wool clothing facilitates greater breathability due to its porous construction. An article of clothing can be made with different densities of this wool.

The lower the density the more breathable it gets.

Material Surface

The material offers greater comfort to the skin because of the very fine fibers as compared to regular wool. It is also soft to the touch.


Would it not be tragic if you get zapped by static because of the fabric you are wearing?

Synthetic material tends to generate static when they get wet but unlike these, Merino wool absorbs moisture easily, minimizing static generation. So, the hiker is safe, in case it rains, or snows during hikes in the wilderness .

Merino wool also resists static so the material never causes electrical static sparks or annoys you by clinging to the skin.

Around Fires

Merino wool does not catch fire easily so it is safe around campfires and activity that is crucial for wilderness hiking like making a fire or cooking in the forest.

This material also does not stick to the skin as others do, so it is safer around heat sources. Would this not be a huge plus for you? Certainly, is with me.

Solar Radiation

Woolen materials in general, have to be treated in order to provide UV protection but Merino wool absorbs radiation(source) throughout the UV frequencies.


One rarely hears about allergies to this material. It is more common to hear about allergic reactions like fabric-caused dermatitis to man-made synthetic fibers like Nylon and Polyester.

Dry Skin in Wet Weather

Clothes made of cotton worn as underwear or even as normal graphic tees are absolutely fine for short walks in warmer weather.

When the weather is cold your sweat sticks to your T-shirt to cling to your skin as a cold compress.

This is definitely very uncomfortable and not advisable especially if you are on a long hike far away from any source of heat to dry up. 

Due to the way its fiber is constructed, Merino wool provides excellent temperature regulation. This material has 2 sheaths – the inner and the outer.

The outer sheath repels water while the inner sheath absorbs up to 1/3rd of its weight in water.

When in wet weather, the outer sheath transfers any moisture to the inner sheath thus keeping the skin touching the dry-out sheath. Consequently, it does not feel wet on the skin.

This is also called the moisture-wicking property of Merino wool and keeps you cool during hikes in warm summer weather.

This is another feature of this fabric that you will greatly appreciate when you are away from civilization.

Odor Resistance

Synthetic materials like Polyester and Nylon do not offer any odor protection. In contrast, Merino wool contains wool wax, also called lanolin, which fights any odor-causing bacteria on the skin.

Due to the presence of this substance in the wool, the clothes that are made with this material keep fresh after days of use. Merino wool stays free of bad smells for a long time even after use in really sweaty conditions.

One can use your merino thermals or underlayer of clothing multiple times over a couple of days without getting any bad odors. Now, this is definitely a plus.

Cooling Effects

Merino wool fiber is very efficient at trapping air with fibers. This helps keep one warm since the trapped air acts as an insulator. As a result, this insulating and warming property works even when the material is wet.

Natural Fiber

Merino wool is natural . Made by sheep every year anew, making it a renewable source of this fiber. Since there is nothing artificial in its makeup the wool is easily biodegradable.


Merino wool fiber is very soft in texture and to the touch. Garments made of this material also have the capability of stretching and returning back to their original size and shape, when not being used.

The fiber is safe enough to be worn directly above the skin as it is non-itchy when in direct touch with the skin.

Choose Merino Wool For Warmth That Conquers The Cold

Hikers need to concentrate on enjoying their tryst with nature, exploring and stepping into the wild world around them.

They should not be bogged down with clothing that feels heavy, uncomfortable, or wet on the body.

The benefits of Merino wool fabric for hikers far outweigh the pricey downside for articles of clothing made from this material.

The fabric is of soft consistency and also lightweight. It is also static-free, safe around fires, provides UV protection, odor-free from sweat smells, is non-allergic to the skin, and also keeps your skin dry in a wet environment.

Hikers should choose Merino wool clothing so that they can have a very good time out there without being dragged down by sub-standard or cheaper alternatives.

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