Accessibility is a critical interior design consideration that increases performance level and allows older adults to be independent and physically active in their daily activities. This study used a case study to present a new method of combining ageing simulation with personas through importance-performance analysis (IPA) and supporting the basic activities of daily living (BADL). This study developed a prioritized persona-based (PP-B) model to create accessible interiors in senior housing environments for healthy ageing. This model was constructed based on an ontology framework. The data that was gathered through the self-assessment accessibility questionnaire by 60 older adults and it was depicted in the IPA matrix, which later translated into personas. These personas were simulated with an ageing suit by interior architecture students based on the BADL of accessible senior housing environments. This study was an initial attempt to deal with the complex nature of accessible interior design and its attributes for ageing studies, which are often considered as theoretical concepts and standards. The main innovation of this developed PP-B model was to synchronize interior design knowledge on accessibility attributes and users’ BADL performance along their accessibility importance rankings. Findings are beneficial for interior designers to make human-centred interior design decisions.