The conception and construction of a building's physical form constitute a primary challenge in architectural design. This research investigates the impact of geographical and environmental factors (independent variables) on the formation of the building’s physical body (dependent variable), focusing on the "Zist Jazayer" public residential complex in Sadra New Town, Shiraz. Addressing the research gap regarding the qualitative enhancement of residential structures in this region, the study aims to identify environmental determinants that lead to optimized architectural outcomes. A mixed-methods research design was adopted. The qualitative phase involved gathering theoretical data, while the quantitative phase utilized a researcher-made survey to examine the correlation between variables. Using Cochran’s formula, a sample size of 369 residents was determined through simple random sampling. Data analysis was conducted using Pearson’s correlation test, which confirmed a significant relationship between the independent and dependent variables. Findings indicate that architectural design must be meticulously aligned with regional conditions, including altitude, humidity, precipitation, and indigenous materials. The study suggests that designers should leverage natural energies and cross-ventilation as positive potentials while mitigating adverse factors like extreme temperatures and disturbing winds through architectural measures. Furthermore, micro-climatic analysis and the use of local vegetation are essential for ensuring resident comfort. In conclusion, integrating geographical and environmental considerations into the design process is vital for the qualitative improvement and structural sustainability of residential complexes in the international system of modern architecture.