Multi-objective Optimization of Girih Tile Patterns and Colored Glass in Orosi Windows: A Case Study of Isfahan Architecture

Efficient energy use is vital in architecture, and the building envelope plays a key role in aesthetics, thermal comfort, energy efficiency, and natural lighting. Traditional architecture has employed innovative solutions for building envelopes to address climatic challenges and ensure suitable indoor thermal conditions. One prominent example is the use of Girih tile patterns and colored Orosi windows, which have successfully met the functional and climatic needs of traditional buildings. This study investigates various Girih tile patterns and colored glass combinations in Orosi windows of traditional buildings in Isfahan. Their layout and wood-to-glass ratio were analyzed. Using a semi-experimental, quantitative approach with software simulations, 60 Girih tile patterns were assessed in Rhino7 with Honeybee and Ladybug, and 120 colored glass combinations were optimized via Octopus in Grasshopper. Results show that the optimal pattern (N50), a twelve-sided Safavid design with 58.14% wood density, achieved 88.51% useful daylight illuminance, 99.03% visual comfort, and 99.47% thermal comfort. This yielded the highest overall performance (95.67% average, SD = 6.20). Patterns with 51–57% wood density maintained high optimization, while densities above 59% reduced daylight penetration. For colored glass, combinations with higher yellow content reached up to 87.89% UDI, whereas patterns dominated by colorless and blue glass dropped to 4.58% UDI. These findings provide evidence-based guidelines for designing openings that balance daylighting, visual comfort, and thermal efficiency in Isfahan’s cold semi-arid climate. It is noteworthy that the results of analyzing the performance level of single colors differ significantly from the arrangement of various colors alongside each other.