With the deepening of China's population ageing, the prevalence of chronic diseases and disability among older adults is rising. How to delay the disability and improve the health status of the elderly has become social issues. Data from China's Seventh National Population Census show that in 2020, over 95% of older adults chose home-based elderly care. However, the existing residential buildings in China exhibit insufficient age-friendly home renovation due to outdated building standards and suboptimal spatial planning from earlier periods. To address this issue, China issued the Guiding Opinions on Accelerating the Implementation of Age-Friendly Home Renovation Projects for the Elderly, aiming to improve the quality and capacity of home-based elderly care services by promoting the age-friendly home renovation. However, whether it can effectively promote elderly health still requires further empirical verification.

Based on the data of China Longitudinal Aging Social Survey (CLASS) from 2018 to 2023, this study adopts the two-way fixed effect model to empirically examine the impact, potential mechanism, heterogeneity, and synergistic effect with smart devices of age-friendly home renovation on older adults' health. Grounded in the ICF framework, the study reveals the health-promoting pathways of age-friendly home renovation from physical, social, and psychological dimensions, and its synergistic effect with smart elderly care devices. This study provides practical references for promoting the construction of age-friendly home renovation, developing smart home-based elderly care services, and improving the building of age-friendly environments, thus possessing important theoretical and practical implications.

The findings indicate that age-friendly home renovation not only reduces the degree of disability among older adults but also alleviates the level of depressive symptoms. Mechanism analysis reveals that age-friendly home renovation promotes older adults' health by reducing the risk of falls and social isolation, as well as by promoting positive age identity. Heterogeneity analysis reveals stronger health-promoting effects among older adults aged 75 and above, those in empty-nest households, and those in rural areas. Moderation effect results show that smart devices positively moderate the relationship between age-friendly home renovation and older adults' health. Based on these findings, this study proposes policy recommendations including improving the quality and health benefits of age-friendly home renovation, implementing stratified and targeted renovation strategies, and advancing the deep integration of age-friendly home renovation with smart elderly care.

This study goes beyond previous policy evaluations that primarily focused on community public environments, shifting the unit of analysis to the home environment and examining the health effects of age-friendly home renovation from the perspective of physical and mental health, thereby addressing the limitations in existing research that has paid insufficient attention to the health impacts of family physical spaces. By constructing a systematic pathway across physical, social, and psychological environmental dimensions, this study extends age-friendly home renovation from the traditional “competence-press” fit model toward a new “resource-empowerment” perspective. Furthermore, by incorporating smart devices into the person-environment interaction framework, this study not only expands the analytical framework of person-tool-environment interaction within ecological theory of ageing but also enhances the explanatory power and application value of this theory in the context of smart elderly care.