In the hot-humid regions of South China, it is common for residents to utilize a combination of window opening and split air conditioners to cool their houses during summer. However, existing research focuses on investigating either window opening behavior or air conditioner usage behavior respectively, lacking a linkage study between these two approaches. Addressing this research gap, a novel coordinated regulation behavior model was developed by integrating both window opening and air conditioner usage behaviors. Due to different coordinate regulation modes, the tolerance temperature range in summer varies in mixed-cooling houses. Additionally, a degree of coordination is introduced to signify the level of overlap between window opening and air conditioner usage behaviors, indicating the uncertainty involved in choosing between these two actions. Moreover, residents exhibit a dynamic approach to switching between cooling methods, characterized by a transition range of approximately 2 °C rather than relying on a fixed temperature value. Notably, the simulated energy consumption results demonstrate a significant energy consumption disparity of up to 71 % among different behavior patterns. This study contributes to the academic understanding of the complex interactions between window opening and air conditioner usage and lays the foundation for achieving precise energy consumption simulation of mixed-cooling houses.