Layering is an important part of any outdoor activity, especially if you'll be facing unpredictable weather, colder climates, and harsh environments. Survival in some extreme cases can also depend on not only your choice of clothing but how it is layered.

Some of the terms a beginner to outdoor sports, hunting, hiking, mountaineering, extreme sports, and outdoor training may see tossed about are active layering versus static layering. What does it mean? What are the differences and why are they important?

Your Body

How your body behaves when active (working out, working hard, exerting yourself) and when static (relaxing day, sitting by the campfire, resting) should be noted and lead to your layering decisions. How warm, or how cold you feel during relaxed states or high activity states should be a large influence on how you layer and what you look for in layering to accommodate how each of our bodies deals with being in motion or a static state.

Some bodies heat up quickly and tend to sweat profusely. Some bodies can heat up just as quickly but manage not to sweat as heavily. Keeping yourself comfortable with a 20 lb. pack walking on flat terrain or climbing is the most essential part of layering. Too much, and you cause yourself to sweat even more. Not enough and hypothermia or frostbite are a very real risk.

Where You Go and What You Do

Now you know your body performs in both active and static states, so the next major consideration is to factor in where you are going to be and what you are going to do while layered.

  • Time spent on the hike, trip, or training
  • Temperature
  • Wind exposure
  • Condensation
  • Trail/terrain conditions
  • Weather
  • Moisture exposure (rivers, lakes, rain)

The endpoint to an active and static layering system will be to provide you the most versatile clothing protection for your specific needs.

Active Layering

If you know you will be playing or working hard on the trail during a hike or during a training course, your layering should account for this.

You need insulation when active in the cold. The reason we do is to make sure the energy our bodies expend consuming food will not simply be lost by being conducted to the air without having benefited from it at all. If we don't insulate from the cold, we will need to consume larger, or even huge amounts of food for our bodies to be able to turn it into energy without attacking fat storage and eventually, muscle itself.

The goal will be to layer with a base and mid-layer that will trap air while remaining breathable and moisture-wicking. Air is the best insulator, allowing for very slow heat conduction. The more air trapped between two bodies (our body, air) the better insulation and less energy loss.

As a base layer for active layering, wicking will be extremely important.

  • Wicking – capillary action that moves liquid through a narrow space using opposing forces (gravity versus heat) or the movement of sweat from your base layer or shirt to the outside of the said garment to be dried on a larger external surface. This means the more wicking a garment has, the quicker it dries.
  • Breathability – the movement of air and vapor through a narrow space, such as fabric, or membranes. Most shells, or top layers, will take your sweat and turn it into vapor, which then moves through the fabric to the shell's outside and dries out.

These two qualities in your active layering will be vital in terms of choosing the right base layer and mid-layer insulation.

A mid-layer is especially crucial when in windy conditions, as wind without a shell to block it can simply swoop in and blow away the warmed, insulated air.

Mid-layers should be worn whenever the temperature becomes too low for comfort and you feel you need another air barrier between your waterproof and/or windproof shell (outer jacket, etc.) and your base layer.

Tip: It's easy to overdress and accidentally overheat yourself. If you are just starting an activity, to prevent overdressing and heating, start slightly cold as you will no doubt quickly warm up as you become active. If you find yourself still cold, then put on an active base or mid-layer to prevent becoming too cold.

Static Layering

Static layering is when you are no longer on the move, doing high strain activities or exerting your body. You are at rest, and that is when you should change from active layering to static layering.

Although we mentioned breathability above for active layering, when it comes to static layering, for static—you have more leeway. Especially since you should not be sweating as much or at all at rest, non-breathable insulation can be used here.

In static situations we need the extra insulation as our bodies are no longer generating as much heat and trapping the air becomes more important than breathability. Nonbreathable insulations are made by trapping high loft material such as microfiber, wool, and so on in a pocket using thin, high tenacity synthetic fibers.

For static layering you'll want:

  • Down items
  • Synthetic insulation (tent, sleeping bag, jacket)
  • Wool, alpaca, yak

Three key factors to consider when you are static layering or looking for a good static layer:

  • Thickness – The thicker the garment, the warmer it will be. And most likely, the heavier to carry. If you are going to be in an extremely cold environment during static times, then the thicker the better.

• Weight to warmth ratio: Obviously if you are going to be traveling on foot, the lightest option you can find and afford to get the most warmth out of it will be important.

  • Remember limitations. Synthetic fibers can only be made so thick without them collapsing. Synthetic will never be as thick as down is, however, down is susceptible to humidity and condensation making it a risk in wet environments.

What We Recommend

At Tactical Distributors, we recommend having these basic garments for both static and active layering:

  1. Merino Wool base layer including, socks, tights, shorts, long-sleeved or short-sleeved top. The MTHD Merino line is especially well-loved for this.
  2. Thin mid-layer jacket or hoodie, like the TD Shaolin Hoodie.
  3. A solid, synthetic jacket that can be used for your shell for a break like the Arc'teryx LEAF Alpha Jacket. For cold climates, pick one with heavier insulation, such as the MTHD Ascent Reversible Hybrid Hoodie. Perfect for active layer outer shell.
  4. A very thick jacket for static or state of rest. The TD Down Range jacket, for example, is an excellent, thick jacket.

At the end of the day during any excursion, your goal is to stay comfortable outdoors. You probably can't afford, both price-wise and weight-wise, to purchase 10 different jackets for all the different seasons, adventures, and jobs you do. So, taking the time to understand static versus active and the core elements of these two types of layering will save you time, effort, money, and possibly your life in the long run.