The layering System

dannah layering system

The laying system

Layering your clothing is a tried-and-true way to ensure your comfort in the outdoors. The beauty of this simple concept is that it allows you to make quick adjustments based on your activity level and changes in the weather.

Each layer has a function. The base layer (against your skin) manages moisture; the insulating layer protects you from the cold; the shell layer (outer layer) shields you from wind and rain. You simply add or subtract layers as needed.

Your Base Layer: Moisture Management


This is your next-to-skin layer. More than any other layer, the base layer helps regulate your body temperature by moving perspiration away from your skin. Trapped inside your clothing, perspiration can leave you chilled or damp no matter how well your shell layer fends off rain and snow.

Keeping your skin dry is important for maintaining a cool body temperature in the summer and avoiding hypothermia in the winter. If you’ve ever worn a cotton T-shirt under your raincoat while you walked, you probably remember feeling wet and clammy, even though you weren’t getting wet from the rain itself. Cotton is an example of a fabric that retains perspiration and can leave you vulnerable to unwanted chills.

For outdoor comfort, your base layer should be made of merino wool (popularized by brands such as SmartWool, Ibex and Icebreaker), synthetic fabrics (such as Capilene, PowerDry and CoolMax polyester) or, for a few uses, silk. Rather than absorbing moisture, these fabrics transport (or “wick”) perspiration away from your skin, dispersing it on the outer surface where it can evaporate. The result: You stay drier even when you sweat, and your shirt dries faster afterwards.

Examples: A base layer can be anything from briefs and sports bras to long underwear sets (tops and bottoms) to tights and T-shirts. It can be designed to fit snugly or a loose fitting, fine-mesh garment. For cool conditions, thermal underwear is available in light-, mid- and expedition-weights. Choose the weight that best matches your activity and the temperature.

Your Middle Layer: Insulation


The insulating layer helps you retain heat by trapping air close to your body. Polyester fleece vests, jackets and tights are classic examples of insulation ideal for outdoor activities. They not only trap air but are also made with moisture-wicking fibres to help keep you dry.

Natural fibres such as wool and goose down are excellent insulators. Wool sweaters and shirts (especially the new generation of merino wool products) offer soft, reliable warmth and keep on insulating even when wet. For very cold and dry conditions, goose down is an excellent choice. It offers an unbeatable warmth-to-weight ratio and is highly compressible. Down’s main drawback is that it must be kept dry to maintain its insulating ability.

Classic fleece such as Polartec 100, 200 or Thermal Pro polyester and other synthetic insulations such as Thinsulate provide warmth for a variety of conditions. These are popular insulators because they’re lightweight, breathable and insulate even when wet. They also dry faster and have a higher warmth-to-weight ratio than even wool. Classic fleece’s main drawbacks are wind permeability and bulk (it’s less compressible than other fabrics).

Like thermal underwear, fleece garments are available in 3 weights for different uses:

  • Lightweight for aerobic activity or mild climates.
  • Midweight for moderate activity or climates.
  • Expedition-weight for low activity or cold climates.

Examples: For high-energy activities such as cross-country skiing, biking or running, choose lighter-weight fleece to avoid overheating. Tights or tops made of Polartec 100 or Polartec PowerDry are excellent for this. For very cold conditions, try thicker fleece such as Polartec 200 or 300.

Wind fleece such as Polartec WindPro polyester or Gore WindStopper adds a high level of wind resistance to fleece. It accomplishes this via a hidden membrane, The membrane can affect the breathability and are best used as soft outer garments in dry conditions.

Your waterproof Layer: Weather Protection


The waterproof or outer layer protects you from wind, rain or snow. waterproofs range from pricey mountaineering jackets to simple windproof jackets, but most are designed to block precipitation and hold in your body heat while allowing water vapour to escape. Most are treated with a durable water repellent (DWR) finish to make water bead up and roll off.

An outer shell is an important piece in bad weather, because if wind and water are allowed to penetrate to your inner layers, you begin to cool off. Furthermore, without proper ventilation, perspiration can’t evaporate but instead condenses on the inside of your shell.

Fit is another consideration. Your shell layer should be roomy enough to fit easily over other layers and not restrict your movement.

Fabric Weights

Though classified as “underwear,” every top in this category is appropriate for use as a stand-alone garment. Micro weight and lightweight T-shirts are standard summertime attire for active outdoor types—when hiking, riding, climbing, taking training runs, you name it—and they’re excellent for gym workouts.

When selecting tops and bottoms for use as base layers (actual underwear), anticipate the conditions you’ll face when choosing the heft of the fabric. Here are our general guidelines:

  • Micro weight: For mild to cool conditions.
  • Lightweight: Cool to moderately cold conditions.
  • Midweight: Moderately cold to cold conditions.
  • Heavyweight: Cold, frigid or blustery conditions.

Some people get cold easily. If so, consider choosing a heavier fabric. Just avoid overdoing it. If conditions become unexpectedly mild, a mid-weight or heavyweight first layer could feel a touch too toasty during vigorous activity.

Tip: Always carry a spare micro or lightweight top on my outings. They weight very little and dry very fast. At the end of a sweaty day I can change out of my “motion” shirt and into my “resting” shirt. This allows me to hand-rinse or air-day my motion shirt in preparation the next day. It’s a nice little luxury.

A few words on fit: The warmer the conditions, the looser you want your base layer to be. Snug-fitting base layers keep body-generated warmth close to your skin, boosting comfort in cool conditions. When temperatures heat up, it’s best to let your next-to-skin layers hang loose to accommodate lots of air circulation. If a garment’s advertising promotes an “athletic fit,” figure its fit will be on the snug side.