No matter where you're going or what you're doing, if you're going to be outside in the cold, staying warm and safe always starts with the concept of layers. In general, we're talking three layers: baselayer, insulation, and an outer layer (or shell).
1. The Baselayer: The most important layer
No matter what season you're in throughout the year, your baselayer will always be the most important layer that you wear. If it's summer, your baselayer may be the only thing you're wearing. In the winter, your choice of baselayer becomes vitally important depending on how active you'll be during the time you're outside.
If you'll be constantly on the move – hiking, running, backcountry skiing, or something similar – your biggest concern is actually not going to be staying warm. It will almost certainly be sweat. You need to make sure all that moisture that you are generating gets removed from your skin as quickly as possible. While sweat may help keep us cool in the summer, during the winter, perspiration that soaks our clothing in the winter can cause death due to hypothermia in extreme situations.
So, the first layer for active pursuits should be a comfortably form-fitting baselayer. We want it comfortably form-fitting so it can wick the sweat off of your body and spread that perspiration out across the entire surface of the shirt (or pants, socks, gloves or hat). That expansion over a wide area exposes more of the moisture to the air, increasing its evaporation and keeping you drier. This is why we recommend merino wool and synthetic fabrics that are specifically designed (either by Mother Nature or by man) to manage moisture and our body temperatures. More on that later.
If you're not going to be consistently active – think sitting on a ski lift for long periods of time, watching winter sports from the sidelines or any other reason you may just be standing around outside in the cold for awhile, your needs for your baselayer change a bit to reflect the lack of sweat you're creating. In this situation, we're likely to recommend your baselayer have a more relaxed fit where it can store a layer of heat between itself and your body.
Your baselayer can cover almost every inch of your body, from your socks to the tips of your fingers, depending on just how cold your environment is. Use either merino wool or synthetic fabrics. If you will be involved in any active endeavors whatsoever, we can not stress enough that cotton fabrics are dangerous when used as winter layers because they lose nearly all of their insulation qualities once wet - and even worse, take an extremely long time to dry.
Patagonia Capilene, Smartwool, Icebreaker and Hot Chillys are just a few of the baselayer manufacturers we carry and recommend.
2. Insulation: How warm do we need to be?
The thing about layering is many times we don't have a great idea of just how cold or warm we will be when we head outside. So, we always want to prepare for the worst while knowing we can remove layers to help regulate our temperature throughout the day. We started with the baselayer to make sure we were managing moisture more than anything else. While moisture control remains a goal of every layer we wear, with our mid-layers, or insulation, we also want to make sure we're warm enough to handle what Mother Nature has decided to throw our way.
Insulation layers can be anything from a more loose-fitting version of your baselayer, to a thick, puffy down sweater. And it might be both. The most important thing to remember is that the concept of layers means we want to be able to remove layers if we're getting too hot, or add layers on if we're getting too cold.
As we mentioned during the discussion of base layers, we want to concentrate on materials and fabrics that will allow moisture to pass through, while maintaining warmth. Again, Merino wool and synthetic fabrics are great options here. Down can also be a great option if the shell material surrounding it is protecting the fill from what getting wet. Synthetic down is yet another option. It won't pack down as small as a natural down, but it also won't lose any warmth if it happens to get wet.
We're aiming to create layers of warmth above our baselayer, so you don't want yet another form-fitting layer right on top of the baselayer. You want at least a little gap between layers to help keep heat within your layering system.
If you get too hot, just take off a layer. Get too cold? Put a layer back on.
3. The Shell - or Outer Layer: Do we need protection from precipitation or wind or both?
If the first two parts of our layering strategy are to mainly protect us from the moisture of our own sweat and move it away from our skin, the final part of our layering strategy is protecting ourselves from moisture - or wind - from the outside.
Moisture in the form of rain, snow or sleet can be extremely dangerous if it soaks our clothing and saps our body's ability to keep warm. Wind, just like the meteorologists always talk about wind chill, can have a bone-chilling effect on us in unprotected areas.
So, the outer layer is almost always going to be at least a wind-proof item, or may need to be a completely water-proof fabric depending on the conditions. The differences between the two can come down to something as simple as seams that are either sealed or not against moisture. No matter how waterproof a fabric may be, any time you're sewing it together to make a jacket, or pants, or gloves, or hats, you're still putting holes in that fabric. And holes will leak unless they're sealed.
There are, however, times when we're okay with those holes being able to "leak". If we're running on a cold winter morning when wind is our biggest enemy, we may want to have as much breathability as possible. This is why you'll see features such as "zip pits" and other ways of ventilating your body temperature (and moisture) on many shell pieces. But if you are facing a drenching rain - or even going to be in snow for a long period of time when your own body heat can melt the snow on your jacket - you're going to be looking for something that is completely waterproof.
There are almost a limitless number of options for you to consider when you're going out in the cold. Grab an Alpine Shop outfitter and explain what you'll be doing and we'll be happy to help you stay warm, comfortable, and safe during this and every winter to follow, no matter what activity you're participating in while outside.