Why is Wool Warm to Wear?

One of nature’s most remarkable fibres, wool, has some special qualities. To begin with, wool is fire-resistant. If exposed to high heat, it will burn, but after the flame is extinguished, it will extinguish itself. The moisture included in each and every fibre of wool is the cause. It is also a very strong and flexible fibre. Wool is a rather effective insulator as well. Imagine it as a thermos for your body; depending on your needs, it may keep you warm or chilly.

Why is Wool Warm?

Wool doesn’t absorb heat from your body, which is one of the main reasons it keeps you warm. To put it another way, wool is a bad heat conductor. Although it may seem strange, this is actually a wonderful thing. A skillet transferring heat from a cooktop is an example of conduction, which is the main way that heat moves from one material to another. Wool doesn’t absorb the heat that your body works so hard to produce when it’s cold outside because of its physical characteristics. As a result, your body stays warm instead of your clothes.

Wool fabric also acts as a power insulator. For more than 10,000 years, people have been aware of sheep’s wool’s insulating properties. This miracle is made possible by the cellular and chemical makeup of individual wool fibers. Natural kinks and bends in wool strands trap air to keep your body warm. Because of its reputation for retaining heat, wool is used as a sustainable, recyclable form of insulation in homes and buildings.

You stay toasty without getting too hot. One of the reasons wool can keep you warm even in the rain is that it has the capacity to absorb up to 30% of its own weight in moisture without feeling wet. The fibres’ inherent crimp aids in wicking moisture from the body. Getting this moisture off of your bare skin is essential for staying warm in chilly weather. But the wool fibre also has some additional, more intricate components that help you stay warm while it’s cold outside.

Retains Heat

Wool has various qualities that help it retain heat, which makes it a perfect fabric for winter clothing. There is a reason why animals initially grow it, after all. All animal hair contains the protein keratin, which is naturally present in wool and aids in regulating body temperature. Additionally, wool fibres serve as an insulator by holding air inside the fabric, which helps regulate your body temperature. Since air transfers heat, the heat you could produce when exercising or moving around in general will also be captured by wool, keeping you even warmer.


Keratin, a protein found naturally in hair and wool, forms an additional barrier along wool fibres that also aids in temperature regulation.

Water Resistant

Wool is a fantastic fabric to wear because it is weather-resistant and keeps you warm in the cold. Popular materials like cotton include air pockets that are more susceptible to water absorption; therefore, they tend to absorb liquids quickly. A cotton shirt will, therefore, actually fill up in heavy rain. In comparison, wool does an excellent job of keeping you dry and can often absorb 20% of its weight in water before leaking. This is due to the fact that wool scales are so tiny that they expel liquid when they scrape against one another. It’s interesting to note that this phenomenon deters dirt as well, making wool self-cleaning! Because of this, certain types of natural wool that retain the animal’s lanolin oil can be almost totally waterproof. They have historically been highly favoured by fishermen and sailors because of this.

Wet and Warm

Wool’s ability to keep you warm even when moist is one of the factors that makes it so useful for outdoor clothing and bedding. Due to its high absorbency, which enables it to hold onto moisture for a longer period of time than other textiles before making you feel wet, this is possible. In addition, wool wicks moisture away from your body, preventing chilly, damp surfaces from contacting your skin. Even additional warmth is produced by the fibres’ amazing ability to produce heat when wet. Clothes made of wool may take longer to dry than those made of cotton or linen, but they will keep you warmer for a longer period of time.


Wool responds to changes in body temperature because of small air pockets that circulate heat throughout the fibers. This means that wearing wool will keep you cool when it’s hot and warm when it’s chilly. Because of this, despite the fact that the sheep appear to be hunched and dejected, they are actually entirely dry and warm underneath their fleece.


To sum up, wool has a number of distinguishing attributes and traits, like being crimped, being elastic, and growing in staples. Wool fabrics have more mass than most other textiles due to the crimp, and because the crimp holds air, the cloth retains heat. The way the strands are woven will also affect how warm a wool product will be. A fabric made of a “cool fibre” that is tightly woven may be warmer than a fabric made of a “warmer fibre” that is not as tightly woven. The lofty, durable yarn created by spinning wool fibres into yarn aspires to entrap airy films and prevent them from escaping from your skin. A napped fabric, such as flannel, will keep more still air against your skin than one that has not been napped, such as muslin. Wool retains heat and traps air, like an installation for a house, for example. It totally makes sense why punk and streetwear fans enjoy donning flannels in the fall.

Updated on: 10-Apr-2023


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