On the coldest of days, when you know you’re going to be outside for more than 10 minutes at a time, a quick clothing check can be the difference between a fun outdoor adventure and frigid nightmare.
There’s a surprising amount of science that goes into the clothing we wear. Materials are crafted for specific purposes, such as staying warm or cool and staving off the wind. Here’s how to dress to enhance the body’s natural ability to stay warm.
The most important advice, even if you ignore everything else on this page, is to dress in layers. Layers inherently cross off most of the other items on this list.
Three layers will keep you warm:
- Base — Polyester, silk or some other material with the ability to wick sweat away from your skin. Just don’t use a cotton shirt as your base layer. It will absorb the moisture fine, but it won’t evaporate.
- Middle — This is the insulating layer, which is the workhorse in keeping you warm. Sweaters, sweatshirts, fleece; these will all work as the middle layer. It should be snug but not tight. Down coats also make a great middle layer in the coldest temperatures.
- Outer — This layer is less about keeping you warm (the first two layers should be doing that) and more about blocking the wind and rain. If it’s not that windy and it’s not raining, a regular winter coat (down puffer, wool pea coat, etc.) will be fine. But if you really want to stay warm, make your outer layer a wind- and waterproof shell, like a rain jacket. Ideally it has vents around the armpits to allow sweat to evaporate. If you want to get really fancy, the outer shells made of specially engineered materials such as Gore-Tex or Sympatex are rain- and windproof and also breathable.
Probably the most common misconception about dressing warm is that the layers should be tight. But if you think of a layer of clothing as the interface between you and the elements, you can see how a tight shirt is only putting your skin closer to the cold air.
Space will keep you warm: a good-fitting wool sweater, for example, that creates a thin boundary layer of air between your skin and the environment. Your body heat will warm the boundary layer and the sweater will prevent the layer from being blown away from your body.
Moisture is the kiss of death on a cold day, whether it’s from rain or perspiration. Evaporation is a cooling process, and if you’re wet, the cooling process is happening right on your skin.
Avoid getting wet by wearing a base layer that wicks sweat away from your body, such as polyester or silk. Your outer layer should be waterproof, such as a rain jacket, but should also have vents or breathable fabric so your perspiration can evaporate off the interior layers.
Break the wind
Even if the temperature isn’t that cold, the wind can make your time outside miserable. Our warm bodies heat up a little layer of air around us, which helps insulate from the cold. Wind can blow the warm layer away. The best way to counter the wind is with a windproof outer layer, which keeps the warm layer of air next to our skin, where it should be.
Hats, gloves and socks
Protect your extremities by wearing a hat that covers your ears, waterproof gloves and wool socks. If you have a beautiful, thick head of hair, you can get away with earmuffs or a winter headband. The idea that most of your body heat is lost through your head is a myth. The body loses most of its heat through whatever is exposed. Stay covered, and you’ll stay warm.
Materials and what they do
Polyester or polypropylene — This material is basically fine, woven strands of plastic, which sounds horrible to wear, but it actually can give clothing its softness. Fleece tends to be made out of polyester, for example. Polyester and polypropylene are moisture-wicking fabrics, which draw perspiration away from the skin. They make great cold-weather clothing.
Silk — It’s more costly than many other fabrics, but silk is a great material for a base layer because it’s natural and wicks moisture like polyester.
Wool — This is an essential cold-weather material when paired with some polyester layers. A wool sweater makes a perfect middle layer. It does absorb moisture, which is not great, but it stays warm even when it’s wet. The best thing about wool is its ability to trap that warm-air layer next to your skin. It also makes good hats and socks.
Nylon — Nylon is good in outer layers, as it doesn’t absorb much water. It makes for a good poncho or rain jacket.
Gore-Tex, Sympatex or similar — These are engineered, patented materials that claim to be waterproof, windproof and breathable. Most of these live up to the claim. They make great outer-layer jackets for cold weather.
Cotton — Clothing made of cotton is not good for cold weather. It absorbs moisture and traps it next to your skin. Save the cotton for summer, when you might want a little extra moisture to keep you cool.