There’s nothing better than heading out over the weekend for a walk in the Scottish Countryside, that is until the weather comes in or worse still in starts raining. If you’re anything like me, you’ve probably taken a day rucksack packed with a few essential items, but the difference between staying warm and comfortable, and being miserably, cold and wet comes down to selecting the correct base layers.
Base layers are typically thin layers of clothing that come into direct contact with the body, providing the sensation of a second layer of skin. The intention behind wearing base layers, is that they help to maintain the right body temperature whilst at the same time serving to expel sweat away from the skin. It is the base layer function of helping to eliminate moisture from the body, that will prevent you from feeling cold.
Base layers refer to both tops and bottoms with hikers opting to wear one or the other, or both. On top of the layers, you might typically wear wind proof clothing such as a fleece jumper followed by a lightweight waterproof jacket and/or trousers.
Three Main Types of Base Layers
There are typically three kinds of base layer; synthetic, merino wool and bamboo. Cotton is not a material that is generally used for base layers as the fabric tends to soak up sweat from the body, as opposed to expelling the moisture thus causing crucial heat to be drawn out of the body.
It is most typical for hill walkers to wear three layers when climbing. The first being the base, followed by a mid-layer and outerwear. If you are planning to embark on a particularly arduous climb, you may wish to consider foregoing the mid layer and replacing with an additional base layer instead. It would be preferable to wear a combination of two differing fabrics, for example, a merino wool layer on top of a synthetic layer.
Synthetic Base Layers
Synthetic base layers are the most commonly favoured, and for good reasons. Firstly, they are the most competitively priced option of the three available materials. Secondly, they are arguably the best for keeping your skin feeling dry and ventilated. Thirdly, they dry quickly so in the event that any moisture manages to seep through, you will find that your garment will return to its normal state a lot more quickly than a based layer made from merino wool.
Finally, the synthetic base layer is the lightest option of the three. A synthetic layer may not be the most suitable option if you are going to be experiencing extremely cold conditions, but they are perfect for wearing in either hot weather or during highly active pursuits.
Merino Wool Base Layers
A base layer comprising of merino wool is the perfect selection for cold weather. The wool is comprised of air pockets that act as ventilation and fibres that retain heat. Experts claim that the merino wool can keep you warm in temperatures as low as -20 degrees, even if the base layer somehow gets wet. This is why you will often see people wearing merino wool base layers whilst participating in an array of winter sports.
Merino wool base layers only present two disadvantages. The first being that they are usually significantly more expensive than synthetic layers, particularly if they are handmade from pure wool and being sold at the top end of the market. Secondly, they do not absorb moisture as well as a synthetic base layer, meaning that your body could become very sweaty during vigorous exercise.
Bamboo Base Layers
Bamboo base layers are made from a combination of bamboo extracts and other fibres, in particular, cotton. They are a relatively new innovation and are often seen as a great alternative for those who find that wool irritates their skin. Similar to merino wool layers, they are good at retaining heat.
Unlike their rival, however, they do not fray and you can expect a bamboo base layer to last you a long time so it is worth taking into consideration that a bamboo base layer can be a cheaper alternative to its counterpart, the merino wool base layer, and could therefore save you a lot of money. Unfortunately, bamboo base layers are not yet as readily available as the other two materials.
Thickness Vs Warmth
Once you have chosen the material for your base layer, the next decision you need to make regards the thickness of your base layer. Generally, there are three varying thicknesses; Light-Weight, Mid-Weight and Heavy-Weight. Commonly, base-layer insulation is measured in g/m² with lightweight base layers being in the region of 150g/m², midweight between 200-250g/m², and heavyweight can be up to 400g/m².
Whilst your selection often comes down to personal preference on how many base layers you choose to wear (personally, I prefer two thinner base layers, as opposed to one thicker layer), below is a guide to selection depending on the season and activity:
- Spring/Summer Hiking – Lightweight
- Winter Hiking – Lightweight or Mid-weight
- Overnight Camping – Mid-Weight
- Low Level Snow Covered Hiking – Mid-Weight or Heavy-Weight
- Mountaineering or Very Cold Weather – Heavyweight