The Difference Between Light, Mid, and Heavy Thermal Weights

The Difference Between Light, Mid, and Heavy Thermal Weights


Whether you are skiing, skating, or taking a hike through the snow, a base thermal layer is an important part of your active outfit in the cold of winter. A thermal layer sits close to your skin to wick sweat from your body, eliminating moisture and helping you retain heat. Thermal layers come in different weights, and it can be hard to know the difference between light, mid, and heavy thermal weights. This guide will help you choose the best option for your needs.


A lightweight thermal layer is perfect for mild or moderate temperatures. If the weather isn’t too cold and you’ll be fairly active while wearing the layer, a lightweight thermal is a good choice for you. Running and cross-country skiing are two good examples of activities that require this type of thermal wear. You can also use this thermal weight in non-active settings to give you another layer of warmth. This is helpful for those who get cold easily.


A midweight layer is ideal for cold but not quite freezing temperatures. Midweight layers are a good middle ground between lightweight and heavyweight, since they are warmer than lightweight but still cool enough to be worn casually or for less extreme activities. You can use this thermal weight for the same activities for lightweight thermals, but in colder conditions.


A heavyweight base layer is ideal in below-freezing temperatures. These thermals are the thickest and warmest of the three options. Heavyweight thermal layers wick less sweat than lighter weight thermals, but they provide a very warm base layer of insulation. This makes them great for protecting against extreme winter weather and cold winds while you are outside. You could use a heavyweight thermal layer on a winter hiking trip or a similar activity.

Now that you know the difference between light, mid, and heavy thermal weights, you’ll be able to decide which weight is best for your favorite cold-weather activity. Hot Chillys makes thermals for men, women, and children in each of these thicknesses, and we are happy to help you find the perfect winter gear for you.