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Natural Awakenings Milwaukee

Understanding Clothing Insulation

Dec 01, 2018 06:48PM ● By Sarah Koehn

When one hears the phrase: “When in Wisconsin...”, often what follows relates to the local food, drink and sports—or knowing your stuff when it comes to surviving Wisconsin winters. Depending upon the conditions, what you wear can make or break your experience in such an unforgiving climate. Learning about clothing insulation—the different types, the advantages of each, and their sustainability and affect on animals—helps one consider the important factors before making a decision about what clothing to buy.


Down is sourced from the layer of feathers closest to a duck’s or goose’s body (undercoating).

Advantages of down: Down is widely considered to be the warmest and most efficient insulation available, requiring less weight and volume to provide the same amount of warmth.

Fill power and compressibility: Fill power (FP) means neither weight nor density—it refers to the fluffiness of the down. The lighter and more fluffy the down, the greater the fill and the loft. Generally speaking, quality jackets feature fill power ranging from 550 to 1,000, with higher numbers representing greater compressibility which is more desirable. Fill power is measured by placing one ounce of down into a cylindrical tube, then applying a light weight on top for one minute. After the weight is released, the down is measured by volume in cubic inches.

Earth- and animal-friendliness: For those concerned with sustainability and the well-being of animals, there is no easy answer to determine how animal- and Earth-friendly the down in a particular garment is—one must look into the company’s practices. Socially responsible brands often use traceable down, allowing one to trace the exact source of the down that was used to make the fabric. Doing so helps maintain the highest standard of ethics and treatment of animals.


Synthetic is constructed from polyester fibers arranged into filaments to mimic the qualities of authentic down.

Advantages of synthetic compared to down: Synthetic offers superior moisture control and maintains a great deal of warmth—even when wet. Further, synthetic tends to be a more affordable option when compared to down, and is hypoallergenic.

Earth- and animal-friendliness: Synthetic removes the need for animals, effectively removing the concern of enforcing socially responsible practices. Some versions of synthetic utilize recycled materials, but this can decrease the longevity of the garment.


Wool is sourced from sheep. The geographic location of the lambs used depends upon the brand.

Advantages of wool: It is a viable, reliable and sustainable option for insulation, and recent advances in wool technology have made this fabric very soft.

Earth- and animal-friendliness: The wool industry was at one point notorious for an inhumane practice called mulesing, which removes skin as well as wool. For ethical, eco-friendly products, be sure that the products you are purchasing use non-mulesing wool.

Other things to consider:

Thoughtful layering is key. In especially chilly temperatures, the most effective approach to insulation is starting with a wool base layer, incorporating a down or synthetic mid-layer (vests are a great solution if you’re looking for added warmth with less bulk), and finishing with a down or synthetic outer layer, depending on the activity and the weather.

For down and synthetic pieces, learn to identify and understand the difference between sewn-through and baffled construction. Baffled pieces are better for windy conditions because the insulation is contained within tiny little boxes throughout the garment, offsetting the seams, which allows the best expansion of the insulation. Sewn-through is typically better for breathability, but can create cold spots if conditions are particularly chilly—although some sewn-through pieces are reinforced with a backing to enhance insulation.

Yellow Wood is a locally owned premier outdoor gear boutique located at 401 E. Silver Spring Dr., Whitefish Bay. The team at Yellow Wood is dedicated to offering supreme service to help you find gear to make your adventure safe, comfortable and enjoyable.