The Layering System – The Base Layer

We all know that wearing a number of thinner layers offers better versatility helping you stay at the right temperature. However, many people consider this handy tip to be the full extent of the magical ‘Layering System’, but it isn’t.

The true Layering System is far more prescriptive, using three different types of garment in a specific order. From the baselayer next to the skin, to the mid-layer, to the final encapsulating outer-layer, each element has its own job to do. In part 1 of this 3 part series we’ll take a closer look at the baselayer.


The common misconception is that the baselayer’s main job is to keep you warm. In truth their primary task is to move perspiration away from the skin. In a lightweight summer baselayer this eliminates that clammy feeling whilst helping you stay cool.

In colder conditions removing perspiration is even more critical helping to avoid rapid heat loss in periods of inactivity. Baselayers designed for the cold tend to be thicker providing additional insulation and are often referred to as thermals.


Ironically the fabric most of us wear next to our skin (cotton) is the worst thing to use as a baselayer. Cotton holds onto moisture which not only feels unpleasant but can also cool the body dangerously quickly.

The best materials for moving moisture, and those found in most baselayers, are manmade fibres like polyester or polypropylene. A serious baselayer will contain at least 90% of these fibres. Have a quick look at the care label to confirm.

The other main fabric to look for is merino wool. Although it doesn’t move moisture quite as rapidly this natural fibre is favoured by many due to its antibacterial properties. Synthetic fibres can begin to develop odours after relatively light use and need to be washed more frequently. However, merino wool baselayers are almost immune to this effect and can be worn many days on end.


The main feature differences between baselayers are dictated by what season they are designed for. Summer baselayers tend to be short sleeved, use lighter fabrics, and looser fits to help you stay cool and comfortable. On the other hand, winter baselayers use long sleeves, thicker fabrics, and closer fits to maximise insulation. Some even come with zip necks and high collars which can be zipped up for extra warmth, or down for superb ventilation. 

Another common feature to look for are antibacterial treatments on synthetic baselayers. Designed to mimic wool’s odour busting performance there are now a wide range of effective technologies available. If you want the fast drying performance of synthetics, with the odour resistance of wool, check out fabrics like Berghaus Argentium.


Well we hope that’s got you over excited about outdoor underwear. Well maybe not, but at least you can shop our huge range of men’s and women’s baselayers with a little more confidence. Take a look at our mid-layer and outer layer blog posts to get the full knowledge of the layering system.


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