Whatever the weather, we hope that this article helps you to keep warm and dry during the winter months.
To understand what we should be wearing for the great outdoors we should first consider what we need the clothing to provide.
Essentially clothing must provide you with warmth and offer you protection from the elements. Your clothing should enable you to lose as much heat as you are generating to help maintain your natural body temperature or ‘thermal equilibrium’. Rather than wearing lots of warm clothes that will increase body temperature, by reaching thermal equilibrium you will be conserving energy that your body may have otherwise used generating heat or losing heat through sweating.
One of the ways of achieving this is to use a layering system as outlined below. Firstly, you have a base layer (with wicking qualities) and then an insulating layer (that retains your body heat) and finally, an outer shell (that protects from wind and rain). Below is a more in depth look at each of these three layers.
The base layer is in direct contact with your skin so it is important that it can adapt well to constant sweating and cooling. Whilst materials like cotton tend to soak up and retain moisture, other fabrics that work well as base layers include natural fibres such as silk or wool or synthetic fibres such as polypropylene or nylon. We would advise wearing natural fibres like wool as synthetic fibres tend to smell after activity! Merino Wool is a material we could highly recommend as a base layer.
Some of the common qualities of base layers are:
– They are made from light fibres that are also very durable.
– The materials absorb only a very small percentage (less than 1%) of their weight in moisture. This enables them to retract moisture from skin and dry very quickly also known as fast wicking.
– The problem with synthetic materials such as polypropylene or nylon is that they start to smell more than the natural fibres do.
The main purpose of the insulating layer is to retain your body heat. They work by trapping a layer of ‘still’ air around your body.
Fleece: A common material used for the insulating layer is fleece. A dense knit of polyester fabric is passed through a ‘napping’ machine which basically creates a solid weave on one side of the fabric and a fluffy side on the other that retains the still air layer.
Similar to fleece is pile. This is a much thicker fabric.
Down Jackets: Many a down jacket can be seen on blustery days at climbing crags. These are great for keeping you warm, a bit like wearing your duvet, but there is a downfall to these, in that they loose their insulting values when wet. There is also synthetic insulation such as primaloft which doesn’t have the same warmth to weight ratio as down but does keep most of its insulting qualities when wet.
Outer Shell Layer
The main purpose for the outer shell is to protect you from the elements by being both waterproof and wind resistant whilst still being breathable.
Waterproofs: These can range from lightweight (for running, rambling etc.) to high tech specialised jackets that are created specifically for mountaineering or snow sports. Choosing a jacket that is waterproof (such as a PVC rain coat) may keep the rain out, but without the benefit of breathability you could become soaked in your own sweat.
Laminated Outer Shells: Materials such as Gore-tex provide a combination that is both waterproof and breathable. It is made by laminating a waterproof membrane to different fabrics. The membrane itself has about 9 billion pores per square inch and each pore is around 20,000 times smaller than a water droplet. So the fabric is able to block out rain and wind whilst allowing body moisture to escape. Although Gore-tex is windproof it doesn’t have any insulating qualities, which is where the other layers mentioned come in.
You may also want to think more about the colour of your outer shell as bright colours are easy to spot in emergency situations.