Understanding homeowners' behavioural determinants: A study on house retrofitting and PV adoption

Decarbonising the residential sector is essential for transitioning cities towards net-zero. Homeowners' adoption of low-carbon technologies (e.g., PV panels and building insulation) is strongly influenced by their behavioural determinants: beliefs, attitudes, and norms, which are often misaligned, contrasting, and irrational. Policymakers promoting the adoption of low-carbon technology in the residential sector should therefore consider the whole spectrum of behavioural determinants. So far, the literature has mostly adopted a deductive quantitative approach with an explanatory or validation aim. This paper aims to complement the existing literature by adopting an inductive qualitative approach. Leveraging 44 semi-structured face-to-face interviews, we aim to explore behavioural determinants underlying low-carbon technology adoption and the mediating role of national incentives. Leveraging the theoretical lens of the Theory of Planned Behaviour we found that an individual homeowner may simultaneously hold ambivalent beliefs about low-carbon technologies, associating them with other technologies perceived as hazardous due to well-known or media reported incidents because they perceive them as relatively new and unfamiliar. Also, low-carbon adoption is not driven by social pressure but rather by isomorphism. Finally, national incentives have a limited effect on adoption as they are just one factor influencing adoption decisions, which are also shaped by behavioural determinants that may be antecedents of economic considerations. Consequently, national incentives may encourage free-riding behaviours, potentially leading to social injustice.