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Even with all the breakthroughs in synthetic fiber technology, wool is still the reigning champ in outdoor insulation. stainless steel fiber metal wire
Innovation and progression are two (probably over-used) popular descriptors applied to the outdoor industry and its associated gear, apparel and accessories. Each new product release is positioned as a breakthrough, an innovation or a monumental step forward in the world of hiking boots, technical outerwear, ski gear and more.
But, in this innovation arms race, classic materials like wool hold their own. I'd argue, for many reasons, wool is (still) the best material used in outdoor apparel. And I'm not alone: brands like Filson, Icebreaker and Arc'teryx (to name a few) have dedicated themselves to producing high-end, quality wool products that will stand the test of time. Here's why placing your bets on wool is a smart move:
Sheep grow wool as a natural protective barrier against cold (and heat, but we'll get to that later) and it's hard to argue with the logic of nature. Wool insulates so well thanks to its structure: each wool fiber is composed of protein molecules, which trap air and moisture, keeping skin temperature stable. Because it's breathable, wool allows moisture vapor to escape while retaining heat. Unlike cotton, which traps moisture against the skin and in turn makes you feel colder, wool can absorb more than 30 percent of its weight before it becomes damp, making it an ideal material for baselayers.
A common misconception with wool is that it's meant to be worn only in cold temperatures. Thick, wool will overheat you in warmer temperatures. However, wearing a thin layer of wool on a hot day can actually help you beat the heat. Wool is moisture-wicking, quick drying and helps regulate skin temperature; these are all qualities you'd want in a summer sun shirt.
Wool's unique cellular structure comes with a laundry list of benefits, including its natural antimicrobial qualities and odor-resistance. Wool's fibers have a distinctive overlapping structure which sort of acts like shingles on a roof — the overlap keeps dirt and moisture on the surface, which helps to combat the bacterial or microbial growth which produce unpleasant odors.
There's a reason many folks have wool blankets or jackets handed down from grandparents and parents that they still use, and it's not because previous generations were overly-cautious with their wool products. It's because the fiber is durable and long lasting, and when constructed properly into a garment or blanket, can last for generations. According to American Wool, there's science to back up these anecdotal hand-me-downs: "Wool items last because wool fibers can bend up to 20,000 times before breaking. This durability far surpasses other fibers, making wool tough to tear and resistant to abrasion."
Just because something is good — or great — enough as-is, doesn't mean it can't be improved upon in some measures. Plenty of brands have wool and synthetic proprietary blends, putting their own stamp on the popular fiber. Here are a few of my favorites:
The brand's proprietary wool blends non-mulesed wool with polyester for wind and water resistance, as well thermal efficiency. Polyester adds stretch and movement to already durable and weather-resistant wool.
Smartwool's Merino 150 is made with Core Spun technology where merino fibers are wrapped around a nylon core to increase durability while still keeping the comfort and benefits of merino next to your skin.
conductive tape Zoneknit is Icebreaker's solution to wearing merino wool year-round. Engineered, body-mapped mesh panels allow for breathability and temperature regulation, and off-shoulder seams prevent friction. Icebreaker included Cool-Lite in this design, which combines the comfort and breathability of merino with tencel, a natural wood fiber made from sustainably-sourced eucalyptus.