The sacred privacy of the house is regarded as the core of family unity and its primary refuge. The principle of privacy (ḥurmah) constitutes one of the fundamental aspects of the Islamic worldview, deeply embedded in the social life of Muslims and counted among the most significant moral and cultural values. In the Qur’an and the traditions of the Infallible Imams, the observance of privacy and respect for the sanctity of domestic space have been emphasized as essential requirements. Within Islamic architecture, this principle has consistently attracted the attention of architects and has been observed in the construction of houses, the most intimate spaces of residents’ lives. This study investigates the architectural devices employed to ensure privacy in Qajar-period houses of the Pāyin Khiyābān neighborhood of Mashhad, correlating them with Qur’anic verses and the traditions of the Infallible Imams, and explores their impact on the formation of domestic spaces and the preservation of privacy within them. The research adopts a descriptive-analytical method based on library sources. By examining scriptural references related to residential architecture and identifying architectural elements that foster privacy in the Qajar houses of Pāyin Khiyābān, the manifestation of the principle of privacy is revealed in both visual and auditory dimensions through strategies such as spatial orientation, introversion, and hierarchical organization—all of which are consistent with Islamic teachings.