Guide: The Multi Layer Principle
Guide: The Multi Layer Principle
During longer outdoor stays, appropriate clothing is crucial. In changeable weather conditions, or if you plan to engage in activities with varying levels of exertion, it's important that the garments you wear are well-suited to each other and allow for good versatility.
By dressing in multiple thin layers, you can assemble a combination of clothes that you then adjust to prevailing weather conditions and that effectively ventilate excess body heat considering the activity you're engaged in. This concept is called the layering principle.
The multi layering principle is a model that describes the different layers we use in a clothing system. It explains the various characteristics the different layers should have and the functions they serve.
The Four Layers
Applying the layering principle doesn't mean you always have to wear all layers; rather, it encourages you to vary your clothing according to environmental factors such as temperature, wind, and the level of physical exertion. The layering principle also involves being able to utilize each garment's specific features such as hoods, pockets, and ventilation optimally so that the different layers actively work together.
Layer 1: The Inner Layer
The inner layer is the underwear we wear closest to the body, whose primary task is to transport moisture away from the skin to keep it warm and dry. During autumn and winter, we recommend woolen base layers. Wool has superior properties when it comes to managing external temperature changes and the body's own excess heat produced during physical exertion, which turns into moisture.
Layer 2: The Mid-layer
The mid-layer often consists of lighter jackets, sweaters, insulated pants, and slightly thicker base layers that create air pockets for insulation. Additionally, it absorbs/transports moisture from the body through the air exchange that occurs between the different layers when we move. Here, you also want to have the ability to open and close zippers, use a hood, and drawstrings to regulate body heat.
Thinner insulated jackets, fleece sweaters, and shirts work well as mid-layers. Garphyttan's mid-layers are made of polyester or cotton. Polyester is a synthetic material that doesn't retain moisture within the fibers, giving the garment good moisture-wicking properties. Cotton, on the other hand, absorbs a lot of moisture and therefore works well in combination with a wool base layer. It's important to regularly change out a cotton garment as they will cool you down when they become damp.
Layer 3: The Outer layer
The primary task of the outer layer is to protect the underlying layers, which means you ideally want garments that are versatile and durable. They should also be spacious and allow for good freedom of movement.
It's advantageous to be able to open and close zippers, use hoods, and drawstrings to regulate body heat. The pockets on jackets and pants also play an important role in the layering principle. In them, you should be able to store some of your reinforcement garments or even two smaller water bottles. Filled with warm water, drink bottles act as heat sources, helping you maintain body heat when you're engaging in lower-intensity activities in cold conditions.
Jackets, anoraks, and pants made from a cotton/polyester blend have long been one of the more cost-effective and functional solutions for a strong and durable outer layer. Cotton/polyester also has the advantage of being easily impregnated with beeswax, making the material more water-repellent while also lasting longer. Learn more about how to wax your outdoor clothing here!
Layer 4: The Reinforcement Layer
The reinforcement layer is typically divided into two categories – those that protect against strong winds/more persistent moisture and those that provide thermal insulation. These layers are used more selectively when you want to feel comfortable during breaks, overnight stays, or if you were to find yourself in an emergency situation.
As reinforcement, you can also have extra socks, a hat, a scarf, a sweater, a jacket, or a pair of pants. Several of these garments are part of the mid-layer but can be classified as reinforcement layers, depending on the situation in which they are used. Also, consider your sleeping bag or other protection, such as a tent or hammock, as important reinforcements when thinking about the layering principle.
Fit - things to consider
Having airspace between your layers increases the garments' ability to keep you warm. Since air poorly conducts heat, the warmth remains trapped within and between the layers. Therefore, avoid dressing too tightly.
However, some air exchange is important because stagnant air can easily become moist, especially when you're physically active. The exact duration of heat retention depends on the properties of the materials, the chosen combination, and your ability to apply the layers effectively. If you choose overly tight clothing, gloves, or shoes, you limit the space for insulating air. Also, avoid oversized clothing as it may make it difficult to warm up the air, which can make them uncomfortable to wear.
Change clothes if you get wet
In many situations, the surrounding temperature can fluctuate between hot and cold, for example, when moving from an indoor to an outdoor environment. Additionally, your physical activity level may vary in intensity. In these cases, you risk becoming damp or even wet, both from the inside and outside. Wet or damp clothes lose their thermal insulation properties to varying degrees depending on the material they're made of.
Regardless, the risk of cooling down increases. Therefore, it's important to quickly change into dry clothes. Most importantly, change your underwear (inner layer) to keep dry against your body. Always make sure to have an extra base layer stored dry in a waterproof stuff sack. This ensures a good night's sleep, and in emergency situations, it provides good safety.