What to Look For in a Baselayer

A baselayer is an essential piece of technical hiking gear, designed to provide warmth and moisture management while allowing you to move freely in your other layers.baselayer They come in a wide range of weights and materials, from lightweight designs for summer hiking to heavyweight options for frigid resort days. They also feature a variety of technologies, including Polygiene StayFresh anti-odor protection.

How thick and warm you need your baselayer depends on the temperature, how hard you’re working, and the conditions you’ll be facing. While it’s tempting to go with the warmest option, a thicker layer will prevent you from moving freely and won’t be as effective at keeping you dry.

The material a baselayer is made from will also determine how well it performs. Natural fibres like merino wool tend to be the preferred choice for outdoor enthusiasts, as they insulate and regulate body heat better than synthetic fabrics. However, they can be a little too bulky for some activities, particularly when combined with an outer layer like a wind or waterproof jacket. For this reason, many manufacturers now offer a combination of merino and synthetic fibres to produce hybrid garments that are both breathable and insulating.

Another factor to consider is how breathable your chosen baselayer is. Breathability refers to how well the fabric allows sweat vapour to pass through the fibres. If your baselayer doesn’t breathe well, it will trap moisture against your skin and make you feel cold and damp even when you’re not sweating. The most breathable baselayers will have an open and lightweight weave, as this allows for maximum airflow while still offering the necessary warmth and insulation.

Manufacturers often report the breathability of their fabric in grams per square metre (GSM). This provides a good indication of how well the garment will perform, and it’s worth noting that GSM is only one of many factors to take into account when choosing your ideal baselayer.

Other considerations to keep in mind include the fit and function of your baselayer, as well as its durability and cost. For example, the Smartwool Intraknit Thermal has a performance fit that contours to your body and will hold its shape even when you’re active. This makes it an excellent choice for high-intensity hiking and winter sports, but it’s too snug for casual wear.

For a more casual option, the REI Co-op Merino 185 Half-Zip has a looser fit that’s great for wearing around town or while hiking in cool weather. It’s not as breathable as the Smartwool, but it will do the job just fine and is a lot cheaper. It’s a perfect choice for anyone who wants a high-performing baselayer but doesn’t want to spend a fortune.