Cold Climate Technical Layering
Cold climate destinations requires you to keep warm and dry with out over bulking in material that results in you being too hot for a situation or too cold as you are leaving your jacket or pants off as they are too warm to wear. Getting the garments and layers right is essential for you to be comfortable enough to enjoy your tour.
Layering your clothing falls into 3 categories, base layers, insulating layers and outer shell layers.
The base layer is essentially the layer next to your skin. This layer is responsible for regulating your bodies core temperature and removing perspiration away from your skin. It is essential to remove perspiration away from your skin while maintaining dryness. Incorrect thickness of the base layer or amount of layers can result in over heating and wet undergarments while in cold conditions.
When wearing thermals in cold conditions you should look at the garment weight, this can range from 100 gram weight right up to 300 gram weight or more (light, mid or expedition weight materials). When touring Everest Base Camp or similar ETA guides carry two different weight base layer items in a wool weave (160g & 260g), mid and expedition weight materials. I find wool help fight bacteria and odour better than synthetic garments.
A base layer can range from anything such as sports bras, underwear briefs to long thermal underwear (tops and bottoms) to Lycra tights and T-shirts.
In cool climates choose a majority of your base layers to be snug fitting to help assist in keeping you warm. A loosely fitting shirt can offer you an alternate option for warmer sunny days.
Mid insulation layers
This layer helps you to trap your body heat by keeping that warm body air close to your body.
For mild conditions a warm fleece will suffice however in more extreme climates you will need a fleece layer and an insulated jacket such as a duck/goose down or synthetic down material (these are much better these days being lighter and more compact than the goose/duck filled jackets).
Fleeces should be lightweight made from materials such as Polartec® 100, 200 or synthetics such as Thinsulate® provide warmth for a variety of conditions. They’re lightweight, breathable and insulate even when wet. They also dry faster and have a higher warmth-to-weight ratio than even wool. These are perfect for European adventures in mild spring/Autumn conditions.
Wind proof fleece is also a great option and something you should use in cold conditions such as Everest Base Camp or similar. Polartec WindPro® polyester or Gore WindStopper® are the types of material you should be looking for. These fleeces have a wind proof membrane built into the coat and very little effect the breathability of the material. These fleeces also have a higher warmth-to-weight ratio than wool. Lightweight WindStopper fleeces can be used in places such as MT. Wilhelm, MT. Kilimanjaro, Everest Base Camp and the like.
Synthetic or down fill jackets are the perfect item to go over top of your lightweight fleece in the cold temperature extremes of mountain trekking of European winters and the month either side of winter. Synthetic offers better performance and resistance to damp environments although natural fill down jackets are being layered in water resistance coatings improving their performance in damp conditions. ETA guides prefer synthetic fill jackets.
Shell outer layer
As the name suggests is the last layer you put on however is the first defence to the environmental extremes of wind, snow and rain. In essence the outer shells are jackets and pull over pants. Outer shells can range from pricey mountaineering jackets and pants to simple windproof jackets or ponchos. The amount breathability and perspiration let to escape will be far superior in the more expensive jackets. The most widely known fabric is Gore‑tex and eVent, however there are other high performing technical fabrics available which are both waterproof and breathable.
The thickness of the shell is also an important factor. One layer Gore-tex for example will be a perfect item for running or non trekking tours such as Borneo and Europe. Two layer Gore-tex is the absolute minimum shell required for trekking adventures where you will be carrying a backpack for consecutive days and scrambling over rugged terrain. Three layer Gore-Tex being more expensive is the minimum requirement for mountaineering or someone who will use their trekking jacket frequently before or after one of our adventure tours.
Water-resistant/breathable shells are perfect for European or Borneo history that preform best for light precipitation and active levels. These are less expensive than waterproof/breathable outer shells and are usually made of tightly woven fabrics (such as ripstop nylon) to block out wind and light rain.
Insulated waterproof outer shells have layers of insulation built in such as a fleece lining, down or synthetic fill and a waterproof outer lining making them convenient for cold, wet conditions, but not as versatile for layering in fluctuating temperatures that all of our tours encounter. These garments are only suited to high altitude mountaineering or active arctic adventures. We do not suggest using these on our trekking or climbing tours under 7000m in height above sea level.