Proper layering when recreating outdoors can make or break your adventure. Being a park ranger I have seen many people get themselves into trouble out in the wilderness because they are not dressed properly. Layering requires 3 components: a base layer, a mid layer, and a top layer.
BASE LAYER
The point of a base layer is to wick moisture away from the skin. This ensures that they skin remains dry, and therefore warm/cool. Pick a base layer that: wicks moisture from the skin, traps heat, and dries quickly.
The most important note (in my opinion) on the base layer is to avoid cotton. Cotton absorbs moisture like a sponge. One sweaty day in cotton may leave you feeling cold and damp, instead of dry and comfortable. When cotton gets wet it loses any insulation properties it may have when dry. Cotton traps sweat and water close to your skin, making it harder to regulate your temperature. The inability to regulate temperature is deadly in hot and cold weather alike. You want something that will wick away moisture and keep your skin dry.
So what fabric is best? A moisture-wicking material is essential. Look for recycled synthetic fabrics. These fabrics are not only breathable, but will also keep you dry and regulate your temperature. Good base layers are made from synthetic, wool, silk, or bamboo fibers—more on each option below.
A close fit. You don’t want your base layers to be loose, because they’re intended to act as an insulating layer. Having a loose base layer might allow cold air to circulate near your skin, which defeats the purpose of the layer.
Synthetic Fabrics
Synthetic base layers are often cheaper, which makes them an appealing starter option. The downside to synthetics is that they aren’t naturally anti-microbial, so they can get a bit stinky after a while. They also aren’t as good at insulating heat, so they might not be the best choice for really cold climates.
Choose a synthetic base layer if… you’re headed to a milder climate, you’re a beginner, or you’re doing a sweaty activity. A good choice if you are trying out winter climates for a weekend, but not ready to invest in pricier materials.
Silk
You might be surprised to hear that silk is a great base layer for winter! The benefit of silk is that it is super lightweight and not bulky, while still acting as an effective and naturally wicking insulating layer. The downside here is cost and care, but a well-cared-for set of silk base layers can last you for years.
Choose a silk base layer if… you want an inconspicuous but warm base layer that works well under other clothing, and are willing to pay a bit more. A solid choice for everyday layering or for casual activities.
Merino Wool
Merino wool is one of the best types of base layer you can buy, for good reason. It is the warmest option, naturally wicking, antimicrobial (no funky odors!), and relatively easy to care for. The only downside here is cost, and the fact that wool can be slightly bulkier than silk, which makes it sometimes harder to layer. I will take my merino wool base layer with me to the my grave. I wear it while camping, hiking, at work, going to an outdoor festival.
Choose a wool base layer if… you want a versatile, all-around option, and are willing to invest in a layer you’ll keep for years. You really can’t go wrong with merino layers—just be sure to care for them according to the tag. Many are machine washable these days, but hanging dry will keep them intact for longer.
Bamboo
Bamboo base layers are a fairly new creation, but they’re a great alternative for anyone who wants a vegan option, or if your skin might be irritated by wool fibers. Bamboo materials are also anti-microbial and are often even better than wool or silk for wicking, so they’re a solid choice for sports, too. The only downside to bamboo layers is that they are not as commonly available, and are still pricier than synthetics.
MID-LAYERS
On top of your base layer will be your mid layer. The point of this layer is insulation. The layer should be loose enough to trap air against the body. My go-to mid layer is fleece. What I love the most about the mid layers I have is that I found them at thrift stores.
TOP LAYER
The function of the top layer is to protect from wind, rain, snow. It should be waterproof and warm. I have 3 winter coats: one for everyday use, one for skiing, one for hiking. Top layer pants are often overlooked. I have snow pants for skiing, but I also have a pair of waterproof pants for outdoor activities in the elements.
LAYERING WITH AN INFANT, TODDLER, OR OLDER CHILD
The same layering applies to children. If that child is stationary, like in a stroller or in a backpack carrier, add 1 more layer than what you are wearing. Be sure to regularly check children to make sure they aren’t too warm or too cold. Adjust layers as needed. See my post about layering with a toddler/infant for those colder months outdoor activities.