Objective: Passive architectural design, with an emphasis on reducing fossil fuel consumption and utilizing indigenous and regional architectural patterns, is currently recognized as an important approach in contemporary architecture. Chaharmahal and Bakhtiari Province is located in a cold climatic region of Iran, and its capital, Shahrekord—commonly referred to as the “Roof of Iran” due to its geographical location—has a high potential for absorbing solar thermal radiation. This city contains four introverted historical houses, whose optimal examples can inspire contemporary architects in passive design strategies. Specific objectives of this study include determining the optimal proportions of central courtyards, appropriate orientation, and suitable height-to-width ratios.
Method: his research adopts a mixed qualitative–quantitative methodology. Analyses were conducted using ANSYS Fluent software, in which the studied samples were compared based on the average temperature of the inner walls of central courtyards. According to ten-year meteorological data from the provincial Meteorological Organization, January and July were identified as the most critical months of the year; therefore, simulations and analyses were performed for these two months.
Results: Different orientations of central courtyards can significantly influence the amount of received solar radiation and increase the average temperature of the inner courtyard walls.
Conclusions: Among the studied samples, the Mortazaviha House, in terms of orientation and proportions, demonstrated the highest average wall temperature in winter (16.74 °C), with a courtyard proportion of 1:30 and an orientation of 50 degrees relative to the south, making it the optimal winter model. Additionally, the Azadeh House showed the lowest average wall temperature in summer (29.00 °C), with a courtyard proportion of 1:33 and an orientation of 8 degrees relative to the south, and was identified as the optimal summer model. Therefore, in contemporary designs—such as local or vernacular accommodations—the identified optimal model, preferably suited to this climate (Mortazaviha House), can be selected and implemented.
For future studies, it is recommended that the optimal model be simulated and compared using various contemporary materials within a simulation environment in order to identify the most suitable construction materials.