In days past, dealing with severe cold meant bundling up so heavily that movement was difficult. Fortunately, today, fabric innovations have provided outdoor enthusiasts with an even greater array of options for assisting our bodies in the quest to maintain core temperature. Layering is the key to moderating body heat generated by activity and mitigating the thermometer’s sagging mercury. The concept for layering is to combine garments to create a "system" with properties that optimize breathability, insulation, wicking, rapid drying, wind resistance, water repellency and durability without sacrificing mobility or durability.
The problem facing anyone outdoors is that comfort is a moving target based on our level of activity, the height of the sun and time of year. Early in the morning it can be very cold, but as the sun comes up or activity increases our bodies get warmer, or even too warm. Then, as the day wears on and the late afternoon sun drops low, so do the temperatures. When you throw bone-chilling wind into the mix, the challenge becomes even more daunting. The key to responding to this sliding scale of temperature ranges is flexibility through layering with garments made of high-tech fabrics. In the morning, you begin with a full layering system and then simply remove layers and then replace them as temperatures warm up and plummet at day’s end.
The number one rule for comfort during winter is never use cotton fabrics. Cotton is great for cooling the body down, not keeping it warm. Cotton absorbs moisture and moisture means loss of body heat.
The layer next to the skin is called the base layer, and it’s the most important element because it establishes the foundation of warmth and moisture control. An effective base layer should transport perspiration away from the body. Damp undergarments are the main source of body chill. A wet garment against your skin can transfer heat at a rate up to 25 times faster than one that is dry.
With some fabrics, moisture wicking occurs only where fabric touches skin. Columbia’s EC2® Qwik-Dri™ Comfort Control Technology addresses moisture control and thermal retention in the microclimate between your skin and your base layer. EC2 Qwik-Dri uses negatively charged particles to pull moisture away from your skin and disperse it through the fabric for rapid evaporation. The result is a dry, warm, comfortable microclimate around your body, regardless of your level of exertion or the outside temperature. Quick-Dri is constructed of 56% microfilament and 44% soft, spun polyester and contains an antimicrobial for odor control. An additional construction feature, flat-lock seams, is smoother against the skin.
Another important aspect of effective base layer garments is a fabric that is lightweight and stretchable so that your movement isn’t restricted or uncomfortable. Also, high-tech undergarment fabrics wick moisture away from the body and dry quickly. Base layer garments come in a variety of weights, to be matched with the severity of temperatures and the level of aerobic activity anticipated for the day. Another issue to consider is your body’s tendencies. People who are thin or have poor circulation will be more comfortable in heavier weights than a person who has a little more insulation or better circulation. Synthetic underwear is available in various levels of insulation capacity: light, medium, heavy and expedition weight.
Lightweight underwear is for high aerobic activity and moderately cool temperatures such as skiing on sunny days or hiking in late fall. Medium weight is for optimum versatility, warmth and wicking when participating in activities such as fly-fishing, backpacking, skiing, snowshoeing, hunting or anytime you’re on the move in cold temperatures. Heavy or Expedition weight underwear should be selected for high warmth when activity or movement is minimal and temperatures very cold such as ice fishing, sitting in a duck blind or hunting from a treestand.
Thermal underwear is available in a wide variety of fabrics and combinations of fibers that achieve various degrees of functionality. All are designed to keep you warm and dry, but some fabrics are better at it than others. Generally, the fabrics that are most effective are used in the heavier weight garments. Since the base layer is the most critical, and largely a personal-comfort-level issue, having several weight options at your disposal is a good idea so that you have several to choose from for varying conditions.
The inner layer is primarily used for very cold winter conditions when prolonged exposure to the elements is a given. The primary function of the inner layer is to retain body heat and facilitate the dispersal of moisture that is wicking away from the base layer. High-tech, synthetic fabrics have been developed especially for their wicking and breathable properties. The fit of inner layers should be snug but not too constricting.
Polypropylene will keep you both warm and dry and is generally an excellent value. Until recent innovations were developed, polypropylene had an odor problem, but new anti-microbial (bacteria hating/odor eliminating) weaves of polypro are better than ever.
Bi-component knits such as polyester/wool blends or polypropylene/wool blends are combined to provide both wicking and insulating properties in one layer. The side of the garment against the skin resists water and the outer side loves water and pulls moisture through the first layer of fibers. The negative aspect of this combination is that wool takes longer to dry.
Structurally altered fibers are basically altered polyesters. Their inherent structural properties have been changed, creating weaves and shapes, which actually encourage polyester to absorb water, pulling the moisture away from your skin.
Chemically treated polyesters are often blended with Lycra for increased stretch and fit performance and nylon is included for increased durability. Polyester doesn’t manage moisture well, but when treated with a water-friendly chemical process, moisture is induced to migrate through the fabric to the outer surface where it can evaporate. The problem is that the chemical washes out after a year or two, depending on the number of times it is laundered.
BiPolar polyesters combine the best of both chemical and structural alteration. BiPolar 100 (medium weight) BiPolar 200 (expedition weight) are designed to offer more warmth-to-weight value and wick moisture better. It’s soft, warm and feels good against the skin.
Wool’s well-deserved reputation for being heavy and scratchy has been diminished through new weaving processes and cutting tools. Wool is composed of protein and keratin (sulfur containing fibrous proteins); and these new weaves inhibit bacteria growth as sweat is neutralized. Although it has some negative properties, the good things that wool can do outweigh the bad, especially when combined with other fibers.
The line that separates mid and outer layers can be somewhat confusing until you consider the finer points of a quality mid layer. Synthetic fleece garments are an excellent choice for the mid layer, but you may also consider wool, pile, down-fill or synthetic filled garments such as vests. Fleece fabrics require less care than wool, are lighter to pack and are easier to maintain. High-performance fleece effectively blocks the wind and ultra soft fleece feels like a second skin. Down is an excellent insulator as long as it stays dry and it also compresses well for packing.
The mid layer is another level of insulation that retains body heat and transfers moisture outward. Wool and synthetic fabrics, either individually or combined, provide qualities that are excellent for this level of protection. Both of these types of fibers work well for insulation because their properties create small air spaces that trap warm air. Synthetics are superior to wool for moisture management because they absorb very little water, and have a faster rate of evaporation. Wool can absorb as much as 30% of its own weight in water, which also makes it heavier. For activities with a high degree of exertion you should avoid pure wool garments, and those that are made of all synthetic fibers would be even better.
When choosing a mid level garment consider such features as venting by way of front, armpit, chest or full-length zippers. Select a size that fits properly. Pullover garments are an excellent option, offering maximum versatility for ventilation management. Make sure you have extra room in the sleeves so that they can be pushed up for additional cooling. Zipped T-necks ventilate well when open and insulate the neck very well when zipped up. Again, you want a thin layer of air in between each garment and not too much excess fabric that will bunch up, add weight, cause discomfort and hamper maneuverability. Too much space also allows air to gush out with movement, and excess between layers creates more space than your body can warm adequately. Snug without constriction is the key concept for all layers.
Wind, rain and snow are the three most offensive elements to consider when it comes to selecting an outer garment. Garments that disperse body heat and keep out the elements are constructed of fabrics such as Columbia Sportswear Company’s Omni-Tech Ceramic, but Columbia’s Omni-Tech umbrella of technical fabrics feature three different levels of protection to meet varying needs based on activity and weather conditions.
The problem with basic waterproof/windproof fabrics is that their waterproof properties are achieved by laminating. An increase of waterproof properties is achieved by applying a heaver laminate, which also hampers the fabric’s ability to breathe. Conversely, more breathability equals less waterproof qualities. The unique concept of adding ceramic properties resolves the dilemma by providing superior waterproofness and breathability characteristics, and a high strength-to-weight ratio through densely constructed twill weave of fine denier nylon.
An important issue to consider when selecting an outer shell is choosing one with sealed seams. When fabrics are joined together at the seams, tiny holes are created every time a needle passes through the fabric. Even though thread fills these holes, and even with fabrics that are totally waterproof, rain can seep in through the seams and dampen all garments underneath. Some garments are sealed at only the most critical seams, but Columbia uses a waterproof/breathable tape to seal all seams in their Omni-Tech line.
Columbia has taken a number of different design approaches to maximize garment functionality. Various garments will feature one or more of these concepts, but not all features are found on all styles.
• Skiers will appreciate Columbia’s adjustable powder skirt. This internally adjusted wrap is very effective for keeping out both snow and wind.
• Multi-function pockets large enough to contain items such as a two-way radio, cell phone, sunglasses, wallet or other valuables and have security closures to prevent their loss.
• Packability is a key issue when space is at a premium. Packable garments stuff back into themselves and become a small zippered pouch. These types of garments are very handy when layers are removed and need to be stored in a backpack or kept handy for easy, quick access.
• An effective storm hood should provide full range of motion without compromising peripheral vision. Skiers or bikers who wear a helmet will want to consider making sure that the hood they select will cover their helmet.
• Radial sleeves achieve a full range of motion using carefully constructed shoulders and underarm panels that allow you to raise your arms while the jacket stays in place.
• Radial venting systems are an innovative design concept for jackets and parkas that utilize large venting pockets with pit zips for excellent ventilation with less bulk.
When your core temperature begins to fall, the body’s natural defense mechanism kicks in, constricting the blood vessels in fingers and toes to reduce blood flow and protect the most important organs. When your core temperature begins to fall it is a sign of a problem that can be addressed with your layering system. Reduce ventilation or add another mid layer and your body should be able to regulate properly.
Even with proper layering, to protect outer extremities you need to have a good hat, insulated gloves and boots to avoid the numbing effects of severe cold. Both gloves and boots are available with multiple layers of insulation, windproof and waterproof fabrics. Additionally, glove liners add an increased level of protection for extreme temperatures.
With proper layering, insulated gloves and boots, all you need to do is put your hat on and go outside. A good hat should be windproof, waterproof and insulated. Remember that an estimated 30% of your body heat escapes through your head. In very extreme conditions you may want to use a facemask in addition to a head covering. Some hats have flaps that can be turned down to cover the ears. If not, consider wearing a headband that covers the ears, a toboggan or kvichak cap. Ears are very susceptible to frostbite and should be protected when temperatures fall dangerously low.
An effective layering system has numerous elements and the beauty is in the way each element works individually and in harmony with other garments. You can tailor your individual needs to your own personal comfort requirements and adjust them as the day’s conditions dictate, without having to give up an exciting day in the outdoors because you weren’t adequately prepared. With the proper layers, fabrics and features, there is no place on the planet that you could go and not be confident of being reasonably comfortable.