The aim of this study is to assess the impact of wind pressure coefficients (Cp) on airflow modelling in urban environment, with a specific focus on understanding urban microclimate effects. Using CFD0 software, we modeled wind-building interactions for two contexts: a standalone building and another integrated into its urban context. The Cp obtained by CFD0 were integrated into CONTAM to model internal airflow, facilitating enhanced analysis of ventilation and indoor air quality (IAQ). The results reveal a significant influence of the built environment on Cp, and indicate that air exchange rates show significant variations, underlining the need to take into account the complex interaction between buildings and their environment. Compared with the traditional method of Swami and Chandra, our approach has demonstrated superior performance by delivering improved results, thereby attesting to its effectiveness in optimizing building energy planning and enhancing occupant comfort.