Integration of building envelope with open spaces and greenery to enhance thermal and visual comfort and energy efficiency in office buildings

• It has a critical approach to the occupancy level law in existing buildings. • Provides 50 scenarios with different open and closed space combinations to improve thermal comfort, visual comfort, and energy consumption. • By placing the open space in the entire volume of the building presents a new approach and element in architecture. • Choosing optimal models by comparing numerical data extracted from Grasshopper software. • Optimal models can be used in office buildings and related energy studies. This study assesses the impact of dividing land into built and open spaces, with a particular focus on the addition of green areas, on enhancing thermal and visual comfort and reducing energy consumption in office environments. The findings recommend four optimal design strategies: (1) balancing open and closed spaces across all floors, (2) concentrating open spaces on a specific floor, (3) optimizing the distribution of open spaces on upper floors while maintaining a consistent layout on lower floors, and (4) creating green rooftop spaces to improve lighting and occupant comfort. These strategies aim to increase energy efficiency and improve thermal and visual comfort in office buildings within Yazd's climate. Simulations in this research, conducted using advanced Ladybug Tools, reveal that incorporating open and green spaces into interior design, particularly with optimal orientation and distribution, leads to a substantial improvement in the annual Predicted Mean Vote (PMV) index. Specifically, the proposed models show up to a 67 % improvement in PMV compared to current conditions. Moreover, in conditions with lighting levels above 2000 lux, buildings featuring open and green spaces experience up to a 37 % reduction in glare, thereby enhancing indoor environmental quality. These findings indicate that adding open and green spaces to buildings not only improves occupants’ quality of life but also aids in energy optimization. These strategies can serve as effective solutions for sustainable urban development and environmental enhancement, providing valuable design models for future urban planning.