Parka Wrap: Retrofitting Insulation onto the Existing Walls of Occupied Homes

The research aims to address a critical issue in New Zealand, where a significant number of homes lack insulation within their external walls. The lack of insulation leads to significant energy loss, resulting in high heating costs or a significant burden on the healthcare system due to respiratory illnesses. The research investigates how to retrofit existing homes with external insulation while considering the thermal and hygrothermal performance of the building. The study highlights the Parka Wrap system as a potential solution that has shown a 60% reduction in energy required to maintain a comfortable temperature inside a house. The research also recognizes that existing walls are typically leaky, and the addition of insulation requires careful consideration of water penetration and drainage to avoid damage to structural framing. Therefore, physical testing and software-based analysis have been conducted to develop a robust weathertight assembly with predictable thermal performance. The value of this research is significant, as it provides a solution to retrofit cold houses in New Zealand, reducing the burden on the healthcare system and potentially improving the quality of life for homeowners. Overall, this research is essential and has significant implications for the resilience of New Zealand’s housing stock.