France is experiencing a cold spell and freezing temperatures this week. We had almost forgotten the cold, the warm sweaters, the big warm scarves and the soft socks… To stay warm, some people don’t hesitate to put layers of clothing on top of each other. Indeed, this technique is only effective if you respect the right number of layers and avoid synthetics. To face the cold, the choice of warm clothing materials. Elsa May, textile & CSR consultant and teacher at Esmod Paris, gives us all her advice for choosing the warmest clothes and avoiding shivering.
Polyester, wool, viscose… What clothing materials offer the most warmth?
From an ecological point of view, an essential criterion to take into account today, we should favor natural fabrics and fibers over synthetics as much as possible. You should know “that beyond their non-renewable petrochemical origin, these materials release microplastics during each wash, which end up in the oceans, then ingested by fish, to end up on our plates”, indicates in the preamble Elsa May.
Pure virgin wool
Pure virgin wool is therefore recommended for warmth, because it is an excellent fiber, well known for its very resistant knit. It is particularly appreciated for its thermoregulatory properties, and because it protects from cold winds. However, wool is often mixed with other materials, for maintenance reasons or to make it softer. Always be careful when you buy a sweater, its wool must represent at least 50% of the total composition to maintain its anti-cold properties.
Merino wool
Another clothing material to favor is merino wool for its versatility, both insulating from heat in summer, while keeping the body warm in winter. For example, she is “widely used in base layers in sports clothing for its thermoregulatory, anti-odor, antistatic and hypoallergenic properties”, explains our expert. Very soft, the merino materials absorb moisture while being breathable, “that is to say, they wick away moisture perfectly, they dry quickly and can therefore be worn next to the skin without discomfort even when sweating”, adds Elsa May. If you are sensitive to animal abuse, merino should be certified “mulesing free”it is also rarer, therefore more luxurious and more expensive.
Alpaca wool
For its part, Alpaca wool, even at low thickness, retains body heat extremely well, and in addition to being anti-odor and hypoallergenic, it is also antibacterial, it is warmer than merino wool, because it offers better thermal insulation thanks to its hollow fiber structure. It is therefore perfectly suited for all winter accessories such as hats, gloves, scarves or even very comfortable socks.
Cashmere
Cashmere, for its part, is a natural and durable fiber, ultra-soft and pleasant to wear. It will provide you with insulating warmth against the cold. The only downsides are the price, and washing which must be very delicate. From sweaters to pants to accessories, cashmere has everything to keep you warm this winter.
Velvet
Finally, pants in velvet, flannels, corduroy (corduroy or striped velvet) are generally made from woolly materials, therefore warmer, and the structure of these fabrics itself is often thicker, denser and therefore more insulating. In winter, swap your jeans for very comfortable velvet pants, preferably choose colorful ones to brighten up your look, and ride the current trend.
Polyester, elastane, artificial materials… What synthetic material keeps you warmest in winter?
Synthetic and artificial materials are flooding the textile industry. Although they are polluting, polyester, acrylic, nylon or even elastane often appear on the labels of our clothing. However, should they be avoided when the mercury goes down? Polyester, a synthetic polymer derived from petroleum, is most widely used in the textile industry. It represents approximately 70% of the synthetic textile fibers used in clothing. Whether mixed with other natural fibers or not, this fabric keeps you warm. But be careful, it remains less absorbent than natural fibers (it therefore wicks away perspiration less effectively). The same goes for other artificial materials such as elastane or acrylic.
Can we measure the level of thermal insulation of clothing?
When we are dressed, a microclimate is created between the clothing and the skin surface which fluctuates depending on natural ventilation. The influence of clothing on heat exchange is very complex, but can be analyzed and estimated quite simply. Indeed, in the clothing industry, the unit of measurement for thermal insulation of clothing used is the “clo” (comes from clothes in English which translates to clothes), and is measured in g/m2. A Clo value, “this is actually the amount of clothing insulation required for a resting human to maintain thermal comfort in a room at 21 degrees Celsius”, underlines Elsa May. In practice, 1 clo corresponds to the isolation provided by classic street clothing and usual underwear. In winter, beyond style, trends, and choice of materials, brands take into account the thermal insulation index and design clothing to protect from the cold. This is particularly the case for large pieces with sleeves such as down jackets or parkas, and all technical materials for winter sports or hiking, which must absolutely protect against the cold.