Understanding authenticity is essential for creating enduring architecture; however, due to diverse interpretations and the lack of clear criteria, it has received limited in-depth study and has mostly been confined to the fields of cultural heritage and conservation. Since traditional architecture is regarded as authentic, examining traditional houses across different historical periods can help identify the key components of authenticity.
This study aims to analyze the concept of authenticity and examine its manifestation and continuity in the traditional houses of Yazd during the transition from the Qajar to the Pahlavi period, through a review of scholarly literature and expert perspectives. Identifying architectural changes in traditional houses across these two periods plays a crucial role in understanding the components of authenticity in architectural works. Accordingly, the research focuses on physical (corporeal), conceptual, and semantic evidence within these houses in order to trace patterns of continuity or rupture in authenticity in response to the historical and cultural transformations of the period.
This research employs an applied qualitative methodology based on content analysis. Data were gathered through library research, documentary sources, and field observations. After identifying the components of authenticity through the analysis of documents and expert perspectives, selected traditional houses from the Qajar and Pahlavi periods in Yazd were analyzed as case studies. The evolutionary trajectory of these components was examined using descriptive–analytical and comparative methods to evaluate changes from the Qajar to the Pahlavi period.

The findings indicate that when an architectural element is removed at the level of form, the associated concepts and meanings become imperceptible at the other levels of authenticity. Furthermore, the results demonstrate that many components of authenticity across the three levels—form, concept, and meaning—gradually diminish or disappear in the architectural transformation of houses from the Qajar to the Pahlavi period.