How to

21 June 2016

Moisture Wicking Explained

Moisture wicking is an active process in many kinds of clothing, but it’s particularly important where insulation is concerned. All the warm fluff in the world won’t do you any good if moisture is allowed to soak in from sweat.

Fabric wicking was initially developed as a means of making sportswear more comfortable, although it has extended into many other forms of clothing, from cold weather gear to nightwear for people susceptible to hot flashes. In the context of cold weather, the biggest danger it works against is sweat cooling or freezing against the skin after secretion.

So, how does it work? Well, it’s all down to the shaping of the fibres. Natural fabrics like cotton are excellent at absorbing moisture, but they dry very slowly. They are known as ‘hydrophilic’, or water loving. If that phrase sounds slightly familiar, it’s because you might well own a hydrophobic jacket, one that keeps water out. In order to create the ideal wicking fibres, a middle ground has to be found between these two extremes.

Polyester is a hydrophobic fabric, typically, but most wicking apparel is made of it, this is because of a process which is enacted on the fabric after it is woven. This process essentially enables the fabric to draw moisture up to the surface, away from the skin. It’s the same basic job that a candle wick does, hence the name.

The other way of achieving this is to weave hydrophobic and hydrophilic fibres together into what is known as an intimate blend. In either case, the fibres have to be woven in such a way that spaces remain to let the vapour back through, they have to be breathable. This is why most base layers are moisture wicking, they are the part which will actually be touching your skin, so even if you’re wearing something else on top, the sweat will be moved away from your body enough to lessen discomfort.

Some companies have explored ways to create clothing which wicks away moisture effectively, but also insulates from external cold. Clo-i are a prime example, as the fibres they have developed combine solidity, hollow cavities and shaped weaves in order to wick, prevent migration and retain warmth all at once. Proper insulation is about preventing cold reaching your body from the inside as much as from the out, and wicking technology remains the most significant breakthrough we’ve yet had in that regard.