The importance of layering

The basic concept of winter sports clothing is that several dry layers of clothing will trap heat and provide more comfort and warmth than one single bulky layer.

The layering system simply consists of a base layer, one or two mid layers, and an outer layer.

The layers work as a 'system' because each layer affects the performance of the adjoining garment.

Consequently, there is little point spending money on a highly technical outer layer without considering the base and mid layers.

For the system to work efficiently, look for garments that are:

• Breathable – This allows moisture (i.e. perspiration) to pass through the garment to the outer surface.  This is essential for maintaining warmth in cold conditions as any moisture build up will quickly cool the body down.
• Wicking – Wicking refers to the process of actively drawing moisture away from the inner to the outer surface of the garment. This allows the garment to dry more quickly.
• Light-weight – Less bulky garments allow more movement and versatility.  If you are wearing several light-weight garments it is easy to remove a layer if you get too warm or add a layer if the temperature falls.
• Waterproof – Waterproof properties are essential for the outer layer and can be useful for mid-layers. Fabrics are graded with a waterproof rating showing the permeability of the fabric per mm. Usually the higher the number the more waterproof the garment will be.   

Base layers
The base layer is perhaps the most important layer but it is also often the most forgotten about.

Base layers should provide next to the skin insulation but it is essential that they are also breathable with good wicking properties to actively transport moisture (i.e. perspiration) away from the body. 

Thermal cotton garments are easy and inexpensive to buy but they are unsuitable as base layers because although cotton is breathable, it is highly absorbent. 

This means cotton base layers hold moisture next to the skin and in cold conditions this leads to rapid cooling of body temperature.

Silk and wool used to be a popular fabrics for base layers but like cotton these natural fabrics tend to hold moisture in.

It is now generally accepted that the best fabrics for base layers are specially engineered manmade fabrics such as polyester because they offer superior wicking properties.

Specialist polyester base layers will dry much quicker than most natural fibres so the wearer stays warmer.

Mid layers
Mid-layers provide the extra insulation needed in cold conditions.

As with all garments the mid layer needs to be breathable and able to wick moisture to the outer surface.

Therefore, a cotton sweatshirt might look the part but it will hold moisture in and cool your body temperature, making it unsuitable as a mid layer.

Breathable fleece fabrics are probably the most popular form of mid layer.

Fleeces are increasingly being manufactured with waterproofing properties to allow the garment to be used as an outer layer in warmer conditions.

Merino wool garments are also increasing in popularity. Merino wool will stay warm even when it is wet but generally it does not dry as quickly as some of the synthetic alternatives.