Janus Textile Could Keep you Warm and Cool you Down

Researchers in Belgium have unveiled the design for a fabric that could keep a person warm when worn one way, while cooling them down if worn inside out. Although large-scale manufacturing of the material is not yet feasible, the researchers hope their results will inspire further research into similar fabrics.

When at rest in indoor environments, about half of the heat lost by our bodies is transferred to the surrounding air through conduction and convection. To stay warm, we can simply slow these processes by adding layers of clothing. However, the other 50% of heat loss at rest occurs via infrared radiation from skin and from the surfaces of clothing. Reducing this loss – or increasing it to improve cooling – involves modifying the surfaces of clothing.