Investigating the Role of Local Materials in the Traditional Buildings of Kashan from an Environmental Sustainability Perspective

The traditional architecture of Kashan poses unique features in various aspects, one of which is the use of local materials. Due to the increasing importance of the debate on sustainability and the significant impact of materials on building sustainability, the role of local materials in the environmental sustainability of traditional buildings was investigated in this research. In this regard, first, by studying available references, the indicators showing the environmental impact of materials in different stages of their life cycle, including extraction and production, transportation and storage, construction, operation, demolition, and recycling were collected. Then, through field studies in the historical context of Kashan and library studies, the local building materials were identified and evaluated by the above indicators. Evaluation of each indicator was done with a different method such as collecting numerical data, qualitative analysis, or developing a questionnaire. Finally, based on data analysis using the Likert scale, materials were rated on a 1-5 scale for each indicator in order to perform a qualitative comparison between materials from the point of view of compliance with environmental sustainability indicators. The results of this research show that among the studied materials, including mud, stone, gypsum, lime, plant materials, and metals, mud is the most sustainable material with a score of 83 out of 85, and metals are the least sustainable with a score of 37 out of 85. Examination of existing analyses and the scores obtained shows that the most important factor contributing to the low score of metals is its complex manufacturing process and the need to go through processing stages in the factory, unlike soil, which requires the simplest production method without complex processes for preparation.