The Science Behind Why Fur-Lined Hoods Are So Warm

When temperatures plummet into the single digits, every effort to preserve warmth counts. Much has been written about the fur-lined hood. Is it warmer than a traditional hood? History and science have an answer, and that answer is yes. A recent study took traditional caribou-skin coats with huge fur-lined hoods worn by Inuit people and tested them in a wind tunnel vs. contemporary coats with and without fur on the hood. The fur-lining made a huge difference. Where blowing wind contacts the hood, friction from a collision of molecules creates a thin layer of air called a boundary layer that acts as insulation. A thinner layer means less insulation. The fur lined hood creates a larger boundary layer. The body gives off heat, including from your face. When wind blows by, facial heat is transferred or carried away, making your face and you colder. A hood without fur only slightly decreases heat transfer, while a hood with fur decreases the amount of heat lost, thus keeping your face and you warmer. A typical modern coat sporting a hood with an inch of fur will keep you warmer, but not as warm as a real-fur lining would.