Staying Warm In The Outdoors: Fabrics, Layering & More
Staying Warm in the Outdoors: Fabrics, Layering & More
Winter adventures bring a special kind of magic: the crunching of snow-crusted trails, icy blue skies, and the serenity of a frozen, silent landscape. But feeling cold? Not so magical. Few things ruin an outdoor experience faster than feeling cold. Staying warm isn’t just about comfort—it’s essential for safety and enjoyment.
At The Canadian Outdoor Equipment Co., we’re big believers in wool. Our friends at Woolpower Östersund have spent decades perfecting the art of staying warm in freezing weather, and have produced a very informative pdf on the matter: Cold Facts. Warm Clothing. Today, we’re sharing info from this great resource that dives deep into fabric choices for winter clothing, and the knowledge to arm you, the reader with the knowledge you need to enjoy the great outdoors with confidence and comfort.
Understanding the Science: How Your Body Reacts to Cold Weather
Humans are most comfortable at 27°C without clothing. At this temperature, the body effortlessly maintains its optimal internal temperature of 37°C. However, most environments we encounter vary wildly from this ideal, which is why clothing plays such a critical role.
To sustain our core temperature, the body converts food and water into energy, producing heat. At rest, humans generate about 80–100 watts of energy, but during intense activity, this can increase to 1,000 watts.
When exposed to cold, the body reacts by:
- Reducing blood flow to extremities, conserving heat for vital organs. This is why your hands and feet often feel cold first.
- Shivering, which generates heat through muscle activity.
It is critical to stay dry when trying to stay warm. When the body's internal temperature increases above 37°C, it produces perspiration. While useful in hot conditions, perspiring in cold conditions can prove disastrous, as heat transfers through water (sweat) 25 times faster than through air. This cooling effect can quickly lower body temperature, even to the point of hypothermia.
Another key action to keeping the body warm is to stay hydrated. Cold weather dehydrates the body faster, as moisture is lost through breath, and we often feel less thirsty in colder conditions. Proper hydration supports your body’s natural temperature regulation.
Dressing for the Cold: The Three-Layer System
Clothes don't provide heat — they insulate your body from the outside air, trap the air your body has warmed, and help retain heat as a result. Clothes for cold weather need to do two things: insulate the body to help maintain its core temperature and transport excess moisture away from the skin to reduce the amount of body heat lost through perspiration.
Dressing in three main layers is key to dealing with the cold. No single layer can achieve what a properly designed layering system can. Each layer plays a different role in contributing to the system’s overall efficacy and interacts with the other layers to keep the wearer comfortable.
Worn next to the skin, this layer wicks moisture away to prevent heat loss from evaporation. Choose materials like merino wool, which excel at keeping you dry.
Provides insulation by trapping warm air close to your body. Thicker mid-layers work best for low-activity conditions.
Protects against wind, rain, and snow. A breathable, water-resistant shell allows moisture to escape while keeping external elements out. Look for adjustable ventilation for high-activity periods.
Pro Tip: Don’t forget your extremities! Insulative hats, mitts, and moisture-wicking socks are vital for retaining heat. Properly fitted boots that allow for sock layering can make all the difference to keeping feet warm in any conditions.
Materials Matter: Choosing the Right Fabrics
Not all fabrics are created equal. Understanding their properties can help you make informed choices:
Cotton: Cotton is a strong and resilient fabric, but poor at insulating heat, partly due to its low elasticity, and partly because cotton yarns are compact and contain little air. Clothes made of cotton are soft and comfortable on the skin but the fibre absorbs a lot of moisture - great on a hot summer's day, when the moisture buildup serves to help cool the wearer down, but can be deadly in cold conditions where the same propensity can quickly lead to hypothermia. All the more reason to avoid cotton t-shirts and hoodies as base layers - however, cotton can serve as an effective (non-thermal) shell layer, and if treated with oils and waxes, can be made waterproof.
Polyamide (Nylon): Nylon (trade name for polyamide) is a strong elasticized man-made polymer fibre with good abrasion resistance. It absorbs little moisture and is thus quick drying, with good crease-resistance and stability of shape. Shells made from nylon are strong and wind and rain proof, but not necessarily breathable. Nylon can also be combined with other fibres to increase strength and wear resistance.
Polyester: Polyester is a strong elasticized man-made fibre with good abrasion resistance as well. It absorbs very little moisture but can also be made to effectively wick moisture and perspiration. Garments of polyester are suitable when humidity control and/or good abrasion resistance is required, but are prone to bacteria growth and therefore odours from sweat and perspiration, requiring it to be laundered frequently.
Elastane (Spandex): Elastane is used as a stretch yarn to complement other yarns. It is highly elastic (up to 700%) and gives garments excellent shape stability, fit and stretch. It is also highly washable and withstands both heat and perspiration.
Lyocell (Tencel): Lyocell is a form of rayon, and is produced from wood fibres. Modern closed-loop manufacturing techniques, and less harmful chemicals in the production process make Lyocell a highly eco-friendly textile that can assume a wide array of characteristics and properties, from silky softness to cool linen looks and feels. The fibre is strong and washes well with minimal risk of shrinkage.
Why Wool Stands Above the Rest
Wool is a natural, renewable fibre and has self-cleaning properties.
While most often associated with sheep, wool can also be sourced from camel wool, mohair from the angora goat, alpaca wool from the alpaca, cashmere from the cashmere goat and angora from the angora rabbit. Wool's cellular structure is unique and has several qualities that make it highly useful. The core of wool fibres consists of two types of cells that absorb different quantities of moisture. As a result, one type swells more than the other and they move in constant friction. This gives wool fibres a mechanical, self-cleaning effect.
Moisture on the surface of a textile promotes the growth of bacteria, but the outside of wool fibres stay relatively dry: the core of the wool fibre absorbs large quantities of moisture in the form of vapour while the shell of the fibre repels liquid. The vapour passing through the garment will remove soil particles and odours, and as a result, wool garments do not need frequent cleaning, but rather, can be aired out with very good results in humid weather. Unlike synthetics, odour buildup and bacteria growth is not an issue with wool clothing, and by simply hanging wool garments up and airing them out, they can be refreshed, and made ready to wear again - perfect on long camping trips, or when spending lengths of time in the bush.
Wool wicks away moisture.
The protein nucleus of wool fibres has a water repellent shell that prevents fluids from penetrating the fibre. When humidity is higher inside the wool garment than outside, the wool works hard to absorb the moisture and transport it through the material until a balance is reached. Since moisture is transported to the outside of the garment (wicked away from the skin), heat insulation increases and you stay dry. As a result, wool is an effective base layer wicking material.
Wool insulates against both heat and cold.
Wool has several characteristics that contribute to its excellent insulating properties: the loftiness and scaly surface of the wool fibres, the fatty substance lanolin that surrounds the fibres, and its degree of moisture absorption. The bent, crimpy structure of the wool fibres help to trap large quantities of air and provides good heat insulation. Air between the fibres reduces the conduction of heat in the material, and therefore has an insulating effect against both heat and cold. A large quantity of bends in the fibre provides better insulation. The bending of the fibres also means that there are fewer contact points between the material and the skin, another benefit when it comes to trapping air.
Wool is hydroscopic, meaning that it is capable of absorbing moisture from the atmosphere. Wool also has very high absorption heat, meaning energy is released as water molecules slow down when entering wool fibres. This means, when a wool garment gets wet it actually feels warm. Wool can retain moisture both in and between its fibres, while synthetic materials can only retain moisture either in or between fibres; this means that wool can absorb a lot of moisture before it actually feels wet. In fact wool can absorb 30% of its dry weight without feeling damp or losing its shape, and will warm even when wet - no synthetic or other natural fibre can make that claim.
Wool is hard to ignite.
Wool only catches fire at very high temperatures. As wool is comprised of proteins, and traps vapour effectively, it has fire retardant properties. Once wool catches fire, the flame is not fed, but instead the wool fibres are charred and the fire dies - great news for those who spend a lot of time around campfires.
Embrace Cold Weather in the Outdoors with Confidence.
Staying warm in winter is about preparation, smart layering, and choosing the right materials for those layers. At The Canadian Outdoor Equipment Co., our goal is to equip you with the tools and knowledge to enjoy every moment—whether it’s a snowy trek through the woods or a quiet evening under the stars.
Cold Facts. Warm Clothing
A highly informative booklet available for download that provides detailed information on core body temperature, wind chill, convection, radiation, conduction, evaporation, respiration, wool, synthetic vs natural fibres, merino wool, dressing in layers, Ulfrotte, and Woolpower's operation in Ostersund, Sweden.
