Over the years, I’ve learned that the secret sauce to staying comfortable and warm during outdoor activities is base layers. It’s really that simple. A high quality base layer will keep you dry for hours, which means you can spend more time enjoying the things you love!

What is a Base Layer?

Essentially, a base layer is the very first layer of clothing that you put on (after undergarments) that sits on top of your skin. It creates the “base” of your outfit and can make a huge difference in regulating your temperature and keeping you comfortable throughout the day.

In today’s world, we are fortunate enough to have many different kinds of base layers that are made from different fabrics and are different weights. Let’s dive a little deeper into that.

Base Layer Materials

Merino Wool

Merino wool is by far my favorite material for base layers. Contrary to popular belief, it’s not not itchy or irritating to skin.

Pros: Extremely odor resistant, wicks moisture well, and will retain heat.

Cons: Takes longer to dry than synthetics, fabric will wear down over time if not covered with another layer.

Synthetics

Synthetics have become very popular over time. They are commonly made out of polyester or some combination of nylon, rayon, and polyester and tend to have a good amount of stretch to them.

Pros: They are great at wicking moisture, stretchy, and very durable. They are also typically less expensive than wool or merino wool clothing.

Cons: Not great at emitting odor, so they can begin to stink if you don’t wash them frequently.

Cotton

Cotton should never be used as a base layer, as it does not wick moisture and will become heavy and wet during outdoor activity, which can lead to hypothermia.

Base Layer Weight

Base layers come in several different weights. Typically, people have a set of each “weight” and rotate them seasonally, just like you do with socks, hats, or coats.

Lightweight: The lightest weight. Used in moderate to cool temps. I use these most when the temperature is between 60-40 degrees Fahrenheit, like camping or hiking in the shoulder seasons.

Mid-weight: The most commonly used weight. Ideal for cold temps between 20-40 degrees Fahrenheit. I use this throughout the Winter for mid to high-intensity activities like sledding, snowshoeing, and hiking.

Heavyweight: The heaviest weight made for below freezing temperatures or low-intensity activities like snowmobiling or sitting around a campfire.

Base Layer Fit

To be as effective as possible, your base layers should fit snug on your skin. Some people like to leave extra room for “breathability” but that will ultimately compromise how well your base layers can wick moisture, which means they’re not able to perform as well.

My Favorites

Some of my favorite go-to base layers are:

Lightweight:

REI: has a ton of options for lightweight base layers. They typically go on sale in the Spring and late Fall, so try and snag them when they’re 30% off!

Stio: their basis power wool base layers are the perfect year-round lightweight base layer.

Midweight:

Kari Traa: their “rose” base layer tops and bottoms are my favorite—they come in so many colors and styles.

L.L Bean: their cresta 250 midweight base layers are nice.

REI: check out their merino 185 base layer sets.

Stio: I love their midweight merino wool tops and bottoms.

Heavyweight:

L.L Bean: their heavyweight base layers are well-priced and durable.

If you’re new to the world of hiking or buying outdoor gear, the price of base layers may come as a surprise. But trust me when I say that investing in good gear makes a huge difference in your outdoor experience and will save you money in the long run, because it will far outlast the inexpensive gear that is likely to tear, rip, or break from heavy use. A lot of high-end gear companies (Patagonia, REI, L.L. Bean) have policies that will allow you to return gear that doesn’t perform as it is supposed to.

Happy exploring, friends!