Plaster motifs in the architecture of the historical house of Boroujerdi have been used not only for decoration of the house but as symbols to convey certain concepts. The diversity used in these plaster works is very impressive and expresses the valuable architecture of its era in the city of Kashan. In many historical houses of Kashan, which mainly belong to the Qajar period, stucco motifs can be seen in different areas of the house. This grand house, the house of Boroujerdi, has one of the highest ranks in terms of the abundance and multiplicity of motifs. The main goal of this research is to document as much as possible about one of the most important arts of the Qajar era, plaster art. As the first step, we classified the plaster motifs Based on their form and design. Secondly, we counted the motifs and recorded their locations. Finally, we investigated the hidden symbolic concepts in each motif. The present research was conducted using descriptive statistics and content analysis based on field observations, and matching the data with the concepts obtained from library studies. In this study, various information-gathering techniques such as observation, survey, imaging, and coding were used. Our observation discovered a great diversity of plaster motifs picturing objects, plants, fruits, animals, people, and extraterrestrial beings (Jinn). In addition, there were some filling motifs in the background including Khotai motifs. We were able to find 450 figures scattered in 8 locations, including the entrance, alcove, the north side of the courtyard, the decorative gable, the main hall, and the east and west rooms next to the main hall. The motifs concepts were taken from ancient myths, religious beliefs, professions, and occupations. However, a number of motifs are also created under the influence of Western art.
