A Study on Climate Zoning for Buildings in Saudi Arabia Based on Multi-Objective Optimization Using Design Builder

Global climate change is a severe challenge facing the world today. Saudi Arabia, located in a tropical desert climate zone, requires accurate climate zoning for energy - efficient building design. Based on the Saudi Building Code, this study explores the rationality of the current climate zoning criteria in terms of building energy efficiency and comfort. By integrating U - Value, SHGC, window - to - wall ratio, and shading forms into multi - objective optimization using the Design Builder software, simulations of energy consumption and comfort were conducted for cities in different climatic zones of Saudi Arabia. The results indicate that the current zoning standard, which relies solely on cooling degree day based on 10°C(CDD10), has shortcomings such as large step differences between zones and insufficient consideration of terrain and micro - climate impacts. For instance, Khamis Mushait and Abha have similar comfort levels but are classified into different zones. Gizan, influenced by the Red Sea and mountains, exhibits unique comfort characteristics that significantly differ from the existing zoning. It is recommended to refine the zoning by adding indicators such as altitude and temperature variation range and to use dynamic simulation software to optimize the zoning criteria. This would enhance building energy efficiency and indoor comfort and provide a scientific basis for sustainable development in Saudi Arabia.