Geo-sourced materials represent a promising option, offering both thermal and environmental performance to reduce energy consumption and the use of non-renewable resources. In this context, a previous study, has worked on the development of fired clay bricks and characterized them from a multiphysical perspective. These materials exhibit moderate thermal conductivity and high moisture buffering capacity. To characterize their hygrothermal behavior at the wall scale, a test wall was constructed to simulate both indoor and outdoor climates. This paper investigates the hygrothermal behavior of a fired earth brick wall under typical summer climates in Morocco. The study consists of a numerical analysis conducted using WUFI Pro V6.8. The wall's hygrothermal response to these conditions is analyzed based on the temperature and relative humidity profiles at various positions in the wall, as well as the temperature and vapor pressure distributions. The results show that under a continental oceanic conditions, the wall's capacity to regulate heat and moisture is significantly influenced by its material properties. In particular, the moisture buffering capability of the fired earth bricks helps to stabilize indoor relative humidity levels, thereby reducing thermal and moisture fluxes. Additionally, the wall's response to daily climate cycles is characterized by active heat and moisture transfer within the outer layers of the wall, particularly through sorption-desorption processes.