Thermal wear is the most commonly used undergarments in most parts of the world during winter. Generally, thermal wears refer to inner-wear clothing designed to be worn under main outfit to keep you warm by retaining the body heat in winter seasons.
The performance of these thermal wears depends on various factors such as thickness, Fabric used, air permeability, and wicking.
Through this article, we will quickly go through various factors on performance, fabrics, and other factors that will help you to make the right decision.
Common Type of Thermal Wear
- Pure Cotton Thermal wear:
Pure cotton Thermal wear was widely used a few years back but they are out of fashion now due to heavyweight and bulkiness. They are able to retain body weight due to heavyweight and thickness. Since they are thick they can keep more body heat for a longer period. These are soft and have a good hand feel. Cotton has properties to absorb moisture and hence cannot be worn for a longer period. - Polyester (Synthetic) Thermal wear:
Polyester or similarly synthetic we are less costly and are thin but retain a good amount of body heat as it blocks airflow to some extent and hence the body heat can’t escape out. The fabric does not hold moisture and is easy to maintain. As they do not hold moisture they can be worn for a longer period. Easy to maintain and less expensive these types of thermal wear are gaining market. - Wool Thermal wear:
Sheep wool is one of the material for thermal wear and has an excellent hand feel. It does not hold any moisture and also has good resistance to bacteria and give the best warmth in a cold climate. Woolen thermal wear is highly breathable and can be worn for a longer period and good to have for all types of outdoor activities. They are available as pure and mix with different types of synthetic fabric and are expensive as compared to cotton or synthetic thermal wear.
- Mix Fabric Thermal Wear:
Brands are trying to get the best at the lowest possible cost by giving us mixed fabric which are really good.
Thermal wear performance mainly depend on the fabric and its structure.
Pay attention to that.
We have some quick tips on this below.
Fabric Tips
While buying thermal wear, we generally put lots of effort into its style, fit, and use but we hardly ever put any effort to check it’s fabrics and compositions.
We are okay if they feel it is good. Fabrics used in thermal wear are the key factor that determines it performance and the purpose you are buying it.
Here are some tips to check while buying any thermal wear.
- Weight Of Fabric:
We can broadly classify thermal inner-wear in 3 types depending upon its weight. A lightweight thermal for moderate or cool temperature. It will protect you from the light cold and the good area where temperatures are very cold. These are non-bulky and gives you decent protection. Mid-weight thermal wear are for cold temperature and are good for cold weather like the northern part of India. They are not much bulky and give good protection.Heavyweight thermals are used for much colder temperature where you need extra protection. These are generally thick to keep your body heat retained. - Material Used :
Nowadays more and more material options are available in the market due to technology exchange and imports. You can get woolen, Silk, Cotton, synthetic and mix depending upon your choice and use. Synthetic fibers which have good blend of polyester, spandex, nylon, and Lycra are good options as these synthetic fibers and their blend provide a good amount of heat retention and absorbs less moisture. Cotton has a great hand feel but absorbs moisture and is bulky. Wool is expensive and needs a lot of care. - Strength Of Fabric:
Strength of your thermal wear is equally important and should not be a hindrance to your day to day activity and even your workout. Most of them are strong enough to support you through all your activity but check the strength. - Overall Properties Of Fabric:
Thermal wear will be hugging your skin and you want it to be soft. Check the fabric for its feel, stretchable, moisture-wicking, and good all-around comfort.
High Performance Thermal Wear
High-Performance Thermal Inner-wear are mostly in 2 or 3 layers
Do not get confused with mixed fabric were two or more fabric ware blend together and Layered fabric are those in which 2-3 layers of fabric are pasted, fused, or stitched together.
Three Layer (tier) Fabric – It consists of a surface layer which is the top layer of the garment, the second layer, or the sandwich layer and the inner layer.
Two-layer Fabric – It has the top layer and the inner layer and is most commonly used in thermal wear.
Most of the outer layers are made from cotton, polyester, acrylic, nylon, spandex, viscose fiber whereas the sandwich layer is made from ultra-fine polyester, hollow pet staple fiber, or other materials with good heat preservation performance.
Cashmere and camel hair can also be found in some high-class fabrics. With the development of new fibers, bamboo fibers, lycra, modal, milk protein fibers, or other new materials are added into the fabric production, which increases the performance of the garment.
Features Of High Performance Thermal Wear
- High Heat retention:
The property of heat retention of fabrics is the primary performance for thermal underwear. Factors mainly affecting fabric heat retention effects are materials’ thermal conductivity and fabric air content. - Good Air permeability:
Air permeability of fabrics is one of the most important indicators for wearing comfort of thermal inner-wear. The main factors influencing fabric air permeability are fabric density, fabric thickness, and materials. Fabrics with loose structure have less resistance to the airflow, which means they have better air permeability. Cotton fabrics have good permeability, and wool fabrics are loose with low density. Also, as wool fibers have scales on the surface which are not proper for the inner fabric, therefore, cotton and wool are usually used as the main materials in the surface fabric of thermal underwear. - Good Hygroscopicity:
Clothing fabrics’ hygroscopicity influences the humidity within the human’s clothing sub-environment. High humidity can cause body discomfort. Factors mainly affecting fabrics’ hygroscopicity are materials’ commercial moisture regains and fabric structures. The higher the commercial moisture regain is, the better the fabric’s hygroscopicity is, which means the fabric with high commercial moisture regain is easier to absorb sweat from the body. The common materials used in thermal underwear and their commercial moisture regain (in brackets) are cotton (8.5%), wool (15%), viscose (13%), polypropylene fiber (0%), etc. - High Elasticity:
The elasticity of the fabric is mainly determined by the elasticity of the fiber, which is evaluated by the fiber’s elastic recovery rate. The higher the elastic recovery rate is, the better the fiber’s elasticity is, and vice versa. The common elastic materials used in thermal underwear are wool, polyester, polypropylene, spandex, etc. In terms of new type fibers, bamboo fiber, lycra, and PTT fiber are proved to have great elasticity. Fabric elasticity is not only related to the wearing comfort and garment beauty, but also influences the garment durability. The better the fiber’s elasticity is, the better the fabric’s durability is..
- Low Weight:
The weight of the fabric affects the thickness of the garment, which is determined by the material’s density and structure. Fibers with the low density provide larger coverage with a lower weight. Therefore, they are the ideal materials for light clothing. Because of the low density, wool, polyester, polypropylene, and PTT fibers are usually taken as materials for light thermal underwear. The sandwich layer of the fabric always chooses camel hair, ultrafine fibers, hollow fibers, and cotton blended materials to decrease the fabric density per volume.
Care Tips
Read the manufacturer’s note for specific care instructions. To get the most out of your winter thermal underwear, pay attention to these guidelines:
- Cotton – Wash in cold water to prevent the fabric from shrinking. Cotton takes longer to dry. Allow it to air-dry for best results. For faster results, lay the garment flat on a towel. Avoid hanging them up as the fabric starts to stretch over time and lose its shape.
- Silk – For silk thermal wear, hand-wash or use the delicates option on the washing machine.
- Wool – The requirements to wash wool are similar to those of cotton fabrics. Was in cold water and dry on a towel for faster results.
- Synthetic Fabrics – These fabrics are easy to care for and dry quickly. For best results, wash them inside out. It is safe to wash them with warm water. They are dryer-safe and maintain the original shape even if they are hung out to dry.