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Layering System: The Key to Staying Warm

SAIL

August 5, 2023

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layering system

This fall or winter, don’t let cooler temps keep you from enjoying your hiking, snowshoeing, cross-country skiing, or camping adventures. Make sure you have the right clothes to adapt to any situation, temperature, activity or level of perspiration. Here’s an overview of how the layering system will keep you warm, no matter how good or bad the weather is.

Learn more about the layering system, a technique that involves layering clothes to preserve your body heat:

  1. What is the layering system?
  2. How to use the multi-layer system in different weather conditions
  3. 1. The base layer
  4. 2. The mid layer
  5. 3. The outer layer

Find everything you need to adopt this layering method by browsing our different collections of clothing for men, women and kids.

Women’s clothingMen’s clothingKids’ clothing

 

What is the layering system?

To enjoy your favourite activities without fear of getting too cold or too hot, layering is the way to go! The multi-layer system is made up of at least three layers of clothing: a base layer, a mid-layer and an outer layer, which you pile on, adding extra layers if it gets too cold or taking them off one by one if it gets too hot. These multiple layers are more effective than a single big winter jacket worn with a pair of snow pants.

This is because, in a multi-layer system, each piece of clothing has a specific role to play, working in combination with the others to regulate body temperature and provide maximum comfort. This means there are countless variations of the multi-layer system to suit every situation, depending on the season, the activity and the actual or forecasted weather. The layering system can even eliminate the need to buy a new jacket with each change of season!

How to use the multi-layer system in different weather conditions

The pieces that make up your multi-layer system can change according to the weather and activity, which will impact the amount of warmth and protection you need. If you are layering, you should always choose your garments with the utmost care, as the wrong piece can undermine the effectiveness of the other layers and cause a whole host of problems, from discomfort to hypothermia.

Layering for cold weather

In winter, even the warmest jacket is not enough on its own to prevent you from getting cold when you spend several hours outdoors. The reason is simple: moisture, whether it comes from your body or precipitation, will eventually make you colder if it isn’t evacuated. That’s the beauty of layering; all the different pieces combine their properties to keep you warm and dry.
Warmth retention depends mostly on the mid-layer, which must have the right amount of insulation to match not only the temperature but also the activity. As for moisture evacuation, the base and outer layers are the ones to focus on. The base layer can vary in thickness depending on the amount of warmth you are looking for. Its primary function, however, is to absorb moisture and push it outwards, and this depends essentially on the materials it is made of. The outer layer, for its part, must be able to block snow or rain, yet breathable enough to allow moisture from the layers below to escape.

Layering for rain and mild temperatures

When there is precipitation, your layering system’s ability to withstand the elements becomes most important. A water-resistant outer layer with good water-repellent treatment is protective enough for light rain, occasional downpours, and low rainfall. However, if more severe weather is forecasted, such as heavy or incessant rain, a waterproof jacket will make a more effective shield against the elements. When in doubt, opt for the best protection; that way, you’ll always be covered. The other quality to focus on is breathability, which helps ensure optimal moisture evacuation. Make sure every part of your multi-layer system is breathable, and consider layers equipped with small openings for ventilation.

Layering system for hot weather

Even when it’s hot, layering a few pieces of clothing is always a good idea, as temperatures and weather conditions often change over the course of a day. You can always take some layers off at your destination or even carry them in your bag, just in case. Either way, always consider bringing layers like a light vest in case the air temperature gets cool, a shell jacket to protect you from the wind and rain, or a shirt with a UV protection factor. In hot weather, your base layer can consist only of comfortable, breathable, and well-fitted underwear that can absorb and wick away moisture. The same also goes for any piece of clothing you plan on wearing (or layering): breathability and moisture wicking are key.

1. The base layer

As its name suggests, the base layer is the first piece of clothing you put on before layering others on top of it. Its main purpose is to wick moisture off your skin, which helps regulate temperature and keep you comfortable. A base layer must therefore dry quickly, absorb moisture and wick it away from the fabric.

Materials

Merino wool base layers are warm, breathable, naturally antibacterial and able to absorb a fair amount of water without becoming damp to the touch. Despite sweat and hours spent outdoors, the fabric stays odourless and retains body heat even when wet. This material is ideal for people who tend to sweat a lot and for activities of high intensity or requiring sustained endurance, such as cross-country skiing and snowshoeing.

Base layers made from synthetic fibres absorb moisture well and only in small quantities, so they dry very quickly. Soft and flexible, they stay close to the skin while offering high comfort and ease of movement. Their materials are also resistant and easy to care for.

Weight

The weight of base layers is often used to measure their thickness, which indicates the amount of warmth they provide. The most lightweight base layers weigh around 120 GSM and are made for hot temperatures, while those you should wear when layering in winter and for very cold conditions can reach 300 GSM or more. Ultralight and lightweight base layers (around 150 to 200 GSM) are generally suited for warm to cool temperatures, while midweight base layers (around 240 GSM) are appropriate for colder conditions.

The right base layer for the weather

When layering, the main purpose of a base layer is to wick away moisture, so it’s important to go with a breathable, absorbent and quick-drying piece of clothing. Merino wool and synthetic fibres both pull this off very well. For the same weight, merino wool provides a bit more warmth, making it perfect for cold temperatures. Synthetic fibres, on the other hand, are quicker to dry and can be a great choice for humid conditions. In summer, a featherweight base layer, which is thinner than average, can help maintain a comfortable body temperature by evacuating excess heat and wicking away sweat. If it’s cold, you can also get some extra warmth by wearing a thicker base layer.

Discover more tips in our article on how to choose a base layer.

Women’s baselayersMen’s baselayersKids’ baselayers

2. The mid-layer

The mid-layer is the insulation component of the multi-layer system, the one that helps retain body heat. It’s also the item in your layering that you will most likely remove if you get hot. Mid-layers are available in many different materials, and sometimes feature synthetic or down insulation to provide optimal protection when the temperatures drop.

Fleece jackets

Made from synthetic materials, fleece jackets dry quickly and stay warm even when they are wet. They are also very breathable – perfect for moisture evacuation – lightweight and not too bulky, which makes them ideal for layering. There are many models of fleece jackets on the market, with various thicknesses to suit different needs and preferred amounts of warmth.

Down puffers

Down insulated jackets and vests are very effective at retaining body heat. Because down is ultralight and highly compressible, these items pack nicely into a bag when you need to take them off or if you want to carry an extra layer to be ready for anything. When down fibres get damp, though, they don’t insulate as well, so it is best to save these types of mid layers for moderate weather conditions and activities where you don’t sweat too much.

Synthetic insulated puffers

Puffer jackets and vests insulated with synthetic materials keep their properties even when exposed to sweat or moisture. They generally have great breathability and tend to be very quick to dry. As mid layers, synthetic insulated jackets and vests effectively retain heat (though not as much as down) and let moisture pass through the different “levels” of a multi-layer system to evacuate.

Read our article on the differences between down and synthetic materials to discover detailed information on those two types of insulating materials.

3. The outer layer

The role of the outer layer (or “shell”) in a multi-layer system is to protect you from the elements, blocking the wind and keeping you dry from precipitation. In addition to being weatherproof, it must also be lightweight, compressible, breathable and abrasion-resistant for long-lasting protection. Its internal seams must also be sealed to prevent water from seeping in. Most shell jackets are at least somewhat breathable, and they all (or nearly all) feature a water-repellent treatment that causes water to bead up and roll off the fabric instead of penetrating inside.

Waterproof jackets

Waterproof jackets act as a shield against humidity and offer the most effective protection from rain and snow. Their fabric is often made of 2 to 3 layers of materials bonded together to form a waterproof, windproof and breathable whole. Since the outer layer is the last part of a layering system, it has to be breathable; otherwise, all the moisture driven out by the other layers will stay trapped inside, causing discomfort and heat loss. Look for high-performance materials, like Gore-Tex, for example, that not only block the elements but also let moisture evacuate.

Water-resistant jackets

Water-resistant jackets are very versatile. Sometimes filled with a certain amount of insulating material, they provide good protection from the elements but are not meant to withstand strong gusts of wind, long-lasting precipitation and heavy showers of rain or snow. Their low weight and high breathability make them a great outer layer for medium to high-intensity activities – as long as the weather conditions are moderate.

For more details, check out our article explaining the difference between waterproof, water-resistant and water-repellent.

Women’s shellsMen’s shells

FAQ

Why is cotton not good for layering?

How to layer for outdoor activities?

How tight should a base layer be?

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