Heating up, cooling off: exploring cooling behaviours at home in Aotearoa New Zealand

We explored the experiences of summer indoor overheating and summer cooling behaviours in Aotearoa New Zealand using a postal survey. Limited research has engaged with New Zealander's cooling behaviours due to a temperate climate. However, poor thermal dwelling quality and climate warming mean that summer indoor overheating is possibly an emerging problem. The survey was carried out between December 2021 and February 2022, with 641 respondents in total. Overheating was self-reported by almost three quarters of respondents. Use of passive cooling methods was most common, but active cooling methods (e.g. electric fans, heat pump cooling) were used by almost three quarters of respondents. Of the 65 % of households who had a heat pump, 72 % of these used it for cooling. Research from Aotearoa New Zealand has previously shown low use of energy intensive active cooling methods, indicating a change in cooling behaviours. To limit increased residential energy demand and emissions associated with more energy intensive active cooling, both improved housing thermal performance and behavioural change interventions that prioritise passive cooling approaches are required. We also find significant disparity in overheating, and access to and affordability of cooling to achieve comfortable and healthy indoor temperatures. This inequity requires urgent investigation and policy action. • Residential indoor overheating occurs in New Zealand, reported by 72 % of respondents. • Current cooling measures achieve thermal comfort around half of the time. • Almost three quarters of households with a heat pump use it for air conditioning. • Disparity in experienced overheating and summer energy poverty is observed. • Renters, indigenous Māori, and households with children are at increased risk.