Whether for cooling off in warmer weather, or battling the chill in colder climes, base layers help to create a layer between the body and the environment. In the summer, base layers transfer moisture vapour away from the body to aid in evaporative cooling. In winter, they provide an additional layer of insulation.
Base layers generally come in three styles: lightweight being a thin layer that can easily accommodate heavier layers on top and are often worn while running, climbing or skiing; midweight, which is a warmer first layer that can be worn over the lighter or on its own and offers both insulation and moisture management; and heavyweight, designed for extremely cold conditions and worn over the lightweight base layers and have the loosest fit of the various styles.
When choosing the best base layers, there are several key features that you should look out for:
- It is breathable and not prone to clamminess..
- It reacts to changes in body temperature, so it helps you stay warm when the weather is cold, and cool when the weather is hot..
- It has stretch, to allow for mobility and a snug, close fit.
- It helps prevent odours.
While numerous synthetic and high-tech materials are released into the market that claim to be able to achieve all of the above, none can compare to the simply effectiveness of Merino wool.
Merino versus synthetics
While brands are continually releasing various base layers in high-tech synthetic fabrics, Merino wool remains the preferred material for both designers and consumers. As a natural fabric, Merino wool will also eventually decompose, unlike synthetic materials, making it an environmentally sustainable choice.
Base layers lie close to the skin, and as such it is important that they don’t irritate. Because Merino wool is hypoallergenic, it reduces exacerbation of any existing skin conditions.
Merino wool fights odours unlike synthetics, which tend to draw them in and can require long periods of soaking. Merino wool base layers also offer insulation during the drying process which, depending on the weight or style of loft, can either keep the body cool or warm.