When retrofit programmes meet everyday life: A socio-technical evaluation of retrofit practices in Aotearoa New Zealand

Aotearoa New Zealand's ageing housing stock presents significant retrofit potential, with many homes remaining cold and damp despite government-funded programmes. While these initiatives address technical deficiencies, they often prioritise shallow measures, lack performance-based targets, and seldom reflect household needs and everyday practices. Conventional post-occupancy evaluations remain largely technocentric, focusing on energy and thermal indicators, whereas practice-based studies, though insightful, rarely translate findings into actionable improvements. This study addresses both gaps by testing how socio-technical evaluations, informed by social practice theory and participatory design, can strengthen the alignment between household practices and retrofit programmes. Drawing on professional and householder perspectives from nine case study homes, the research applies a convergent triangulation approach combining indoor environmental monitoring, in-home interviews, and a participatory focus group. Findings show that while retrofits delivered material upgrades, most homes continued to experience substandard indoor temperatures and high humidity. Divergences between perceived and monitored data reflected coping behaviours, affordability constraints, and emotional responses shaping engagement with programmes and household practices. The triangulated analysis revealed how technical, social, and institutional misalignments, such as limited follow-up and weak supervision, undermined retrofit outcomes, while participatory engagement helped co-develop strategies addressing critical household practices, rules, and meanings affecting performance. By embedding participatory methods within a socio-technical evaluation, the study demonstrates how diagnostic evidence can be translated into context-sensitive, co-developed improvement strategies. It advances practice-based retrofit research by integrating relational, organisational, and technical dimensions, offering a transferable framework for policy and programme design. Future research should extend this approach across housing sectors and governance settings.