Exploring health and wellbeing impacts of summer indoor overheating on public housing tenants: A mixed-methods study in Wellington, New Zealand

Indoor overheating is an increasing concern in temperate countries as summer temperatures increase with climate change. Limited research has investigated the effects of indoor overheating in vulnerable populations in countries with temperate climates. Public housing tenants are a group of particular concern as they have limited control over their environment and climate change is increasing the need to adapt to overheating. This study used a mixed-methods approach to explore the experiences of public housing tenants dealing with indoor overheating. Indoor temperature monitoring was conducted in seven public housing units in Wellington, New Zealand from Dec 2023 to Feb 2024, and overheating risk was assessed using the Chartered Institution of Building Services Engineers (CIBSE) methods. Participants were interviewed before and after the summer, and the qualitative data was integrated with the quantitative data to understand the impacts of overheating and the vulnerabilities of public housing tenants. This study identified significant overheating, having pronounced impact on tenants’ health and wellbeing. The study found that prolonged home occupancy, along with preexisting health vulnerabilities and limited cooling options and resources, significantly heightens the vulnerability of public housing tenants to overheating. Passive cooling strategies and behavioural thermoregulation were considered impractical and insufficient for achieving thermal comfort in public housing apartments. The use of portable air conditioners effectively reduced indoor temperatures but was limited by cost and local wind conditions. The study emphasises the urgent need for energy-efficient public housing that ensures year-round healthy thermal conditions for vulnerable populations.