Down filled items are used to provide lightweight insulation to keep you warm. The structure of down allows air to be trapped between its filaments and warmed by body heat to provide insulation for the user.
If down gets wet it clumps together. This causes it to lose loft and insulation as it can’t trap air effectively. When wet, down loses all of its insulating properties, as water conducts heat away from the body up to 25 times faster than air. It will also gain weight and its breathability will be significantly reduced; leaving you feeling cold, wet and uncomfortable.
Down filled items are most likely to get sweaty and wet inside when used in damp or wet conditions. Therefore it is important to stop down filled gear from getting wet by applying Durable Water Repellency (DWR). The outer fabric of your down filled item, as well as the down inside, must be maintained to ensure comfort. Through use it will eventually wear off and need to be renewed with Nikwax Down Proof™.