Whether you’re stuck working outside in winter or actively chasing snow-covered trails, maintaining your body temperature is a key part of staying safe and healthy. Military personnel often have it fairly easy when it comes to cold-weather gear; we’re issued all the clothes for the environment we’ll be in. “Remember to layer” is the advice we always hear about (and if you don’t know how to layer, check out yesterday’s blog post). But not everyone knows that this means more than just putting a jacket over a flannel shirt.
To understand clothing insulation, we first need to understand why layering works. Usually, there are three layers: a base layer (undergarments), a middle layer (varies based on weather), and an outer shell (wind or rain protection). They work together to protect you from the elements—rain and snow, freezing temperatures, and wind. The purpose of the middle layer is to provide insulation – and that’s what this post is about.
You should select your middle layer, which can range from a flannel shirt or fleece jacket, to a heavy coat, based on when and where you’ll be wearing it. The types of insulation used in the middle layer varies. You’ll find jackets made with goose down, duck down, wool, fleece, and synthetic stuffing such as Thinsulate. While each has its pros and cons, they all work the same way: they trap air close to the body and insulate that air from the outside temperature.
It’s important to remember that a key part of insulation isn’t just to keep you warm. It also needs to keep you cool enough to prevent sweating. Generally, any type of moisture degrades insulation, although some materials handle moisture better than others. So let’s explore these options.
Down refers to the fine feathers underneath the outer feathers that keep birds warm in cold, wet weather. Not surprisingly, these feathers provide great insulation and have long been used in winter jackets and blankets. When buying down-stuffed clothing, there’s generally a choice between goose and duck down. There’s little difference between the two, except for cost (goose down is more expensive). Goose down is able to provide slightly more insulation per ounce, so goose down jackets are generally a bit lighter and less bulky. This might be important if the overall weight of your supplies is an issue. But at the same time, down is not good at moisture management. Should you get wet or sweaty, the down will trap moisture and not dry very quickly.
Synthetic stuffing such as Thinsulate is getting better and better at mimicking the insulating properties of natural fibers and is likely to surpass them in usefulness in the future. Synthetic stuffing is made with long strands of polyester fibers that are shaped to trap air in the same way down does. Unfortunately, the coarse nature of synthetic fibers means that they don’t compress as well as down does. This in turn means that an item using synthetic fibers might be a bit bulkier than its down equivalent. On the other hand, synthetic fibers are superior at moisture control. Synthetic stuffing dries quicker and doesn’t lose its insulating properties should it get wet, the way that down does. It is also cheaper than goose or duck down. Synthetic stuffing will work best for people on a budget or those who can expect to get wet while being outside.
Wool, Fleece, and Linen
Not every situation calls for a bulky stuffed jacket. There’s a fine line between staying warm and becoming so warm that you’re starting to sweat. In many cases, a wool, fleece, or linen sweater or jacket with a protective outer shell provides sufficient insulation for cool temperatures that won’t dip below freezing. If you know that you’ll be active and likely to sweat in cold weather, consider smartwool and merino wool. They provide good insulation while also being able to quickly wick the moisture away from your body.
Pro tip: Keep a close eye on fit while you’re purchasing layers.
The base layer and middle layer will generally be close to your normal size, while it’s common to go up a size for your outer shell, which has to accommodate all the clothes you wear. Always keep spare base and middle layers on hand when outside for long periods of time. Should you sweat through or otherwise soak your layers, it’s important to quickly change into dry clothes that allow insulation to work. Keep safe out there and, with this knowledge, be better armed for your upcoming winter!
Disclaimer: The content in this article is the opinion of the writer and does not necessarily reflect the policies or opinions of US Patriot Tactical.