To dress comfortably and warmly during a ski holiday, there are a few essential clothing items and accessories, such as a ski jacket, socks, beanie, gloves, waterproof boots, fleece, etc.
What we often think less about, however, are thermal base layers. We’re not talking about men’s boxers or women’s bras, but clothing worn under your sweater, sweatshirt, fleece, or ski jacket. They are essential for protection against cold and moisture! Discover why they are indispensable and which thermal base layers to pack for your winter mountain trip.
For a good balance between warmth, breathability, and comfort, it is recommended to follow the three-layer system: a breathable, quick-drying layer, an insulating layer that creates a thermal barrier, and a waterproof layer to protect against moisture, cold, and the elements.
Thermal base layers are the perfect solution for an effective first layer. In direct contact with the skin, they are designed to wick sweat to the outside and dry quickly, preventing moisture from lowering your body temperature.
This is crucial because when you sweat while skiing, hiking, or doing other sports, moisture sticks to the skin if the base layer is not suitable. The result: when the wind blows or during a break, you feel cold immediately.
Now that you are ready to put together your ski outfit, how do you choose the right technical base layers? Here are our tips for an effective thermal first layer.
If there is one material to avoid for your thermal base layers, it is cotton, as it tends to retain moisture. In fact, if you shop in a winter sports section, you will rarely find technical garments made of cotton.
Instead, favor synthetic fibers like polyester or polyamide, which wick moisture efficiently and dry quickly. Alternatively, you can choose merino wool, a soft natural fiber known for its thermal regulation, breathability, and odor-resistant properties.
There are also fabrics combining merino wool and synthetic technical fibers, allowing you to benefit from the advantages of both (softness, thermal protection, breathability, etc.). Brands also develop technical fibers with specific technologies designed to offer superior protection against the cold, improve sweat wicking, and enhance comfort and feel against the skin.
For effectiveness, a technical base layer should be close-fitting, even skin-tight. While this may seem counter-intuitive, it is essential for proper moisture management.
It is therefore important to choose a well-fitted cut, ideally made from a stretch material for added comfort. Be careful not to choose a layer that is too tight, which could reduce comfort and freedom of movement or even restrict proper blood circulation.
To make base layers more comfortable and high-performing, brands incorporate technologies and design details that can make a big difference.
It is particularly useful to choose a seamless or flat-seam technical layer if you are sensitive to chafing and irritation.
If you tend to sweat a lot and the temperatures are mild, you may also consider a garment with ventilated mesh zones to enhance breathability (though this reduces insulation slightly).
In both men’s and women’s collections, there are 3 main types of technical base layers for mountain sports activities. Here are the essentials to build your ski or winter hiking outfit.
The long-sleeve top is probably the most common and useful technical base layer. Covering the upper body well, it provides a highly effective thermal and breathable first layer.
Some tops also feature a collar to slightly cover the neck and block wind, while others have a zipper to partially open the top in case of overheating.
Worn under ski or hiking pants, technical leggings provide extra insulation while allowing freedom of movement and are almost unnoticeable.
They come in full-length or ¾ length versions depending on your preference. In all cases, make sure to choose the correct size so the leggings stay in place without squeezing.
Lighter than a long-sleeve top, the technical t-shirt is suitable for intense activity, mild days, or as a first layer during ascents.
Since it does not fully cover the arms, its thermal efficiency is lower, but some skiers find the t-shirt more comfortable and better suited when temperatures are mild.