The aim of this study was to establish sustainable materials as alternatives to conventional synthetics, identify the limitations of personal flotation devices in terms of wearability and propose an inventive solution in the form of a winter jacket that provides inherent buoyancy and insulation. A sustainable hybrid personal flotation device – jacket design was developed incorporating participant feedback, material testing, design development, in-water buoyancy, and thermal insulation and evaporative resistance testing. The jacket was designed to prevent hypothermia from cold water immersion, address flotation posture, and prevent fatalities due to drowning and delayed evacuation during rescue emergencies. Properties like buoyancy, water repellency and insulation were achieved using Hemp, Abaca and Kapok. This research addresses concerns like dorsal head immersion which is a major factor contributing to hypothermia in drowning victims yet is not well addressed in conventional personal flotation devices. The findings of this study act as an essential catalyst to advance the use and research of sustainable materials in the realm of performance design by confirming attributes like effective buoyancy, insulation and water repellency as well as encouraging the wear of life saving equipment like personal flotation devices through an effective alternative product design.