An experimental study was carried out on a full-scale passive building equipped with global and local instrumentation with the aim of characterizing the energy charge and discharge processes and their coupling to the outdoor thermal stresses, especially natural ventilation in the summertime. The characterization of both charge and discharge processes is necessary to understand the thermal behavior of a building. From the measurement campaigns, the coupling between the charge–discharge and natural ventilation was qualitatively highlighted by the dynamics of the convective heat flux at each instrumented surface of the envelope. From the analysis of the experimental data, during the charge process, the floor and ceiling play an essential role in the attenuation of the rising of the indoor air temperature, while the south-facing glazed facade contributes the most to the heating of the indoor air. During the discharge process, the floor surface also plays an important role in the discharge of the envelope elements since the floor is the colder surface of the envelope. A parametric analysis of the coupling was also performed and showed that it is necessary to consider the convective effects on the slab surface, the ceiling, and the glazed facade individually due to their behavior.