As the field of zero energy building design and research continues to progress, the use of data analysis methods is on the rise. These methods are applied to create assessment criteria, compare performance, and aid in design decision making. Decision trees, as a data-driven approach, offer interpretability and predictability, assisting designers in summarizing their design experience and serving as a foundation for design references. However, the current application of decision tree methods in the zero energy house sector primarily focuses on HVAC systems, lacking a comprehensive exploration from an architectural design perspective. Therefore, this study presents an empirical method for building and applying models based on decision trees, using zero energy house cases in severely cold regions of China as samples. Through an analysis of the interactions among various passive design parameters and the use of EnergyPlus for performance simulations, a decision tree model is established. This model aids in determining the recommended combinations of passive design parameters that meet the criteria of low energy consumption. Moreover, feature weighting highlights the most influential passive design parameters on building energy consumption, including the length of the architectural gestalt plane, the roof shape, and the ground thermal resistance. This research provides valuable methods and guidance for the design and construction of zero energy houses in severely cold regions of China.

Building Information Modeling (BIM), as an auxiliary design platform, is increasingly adopted in construction projects. However, it is not widely applied in the collaborative design of zero energy buildings (ZEBs), due to the cross-discipline and complex features of ZEB projects and lack of research on the procedure and method of collaborative design in this field. This paper introduces a BIM-based collaborative design method for ZEBs. From the perspective of the technical requirements of ZEBs, the study elaborates the application of a BIM-based collaborative design method among specialists from different disciplines in passive design, renewable energy utilization and active design. The feasibility of this method is verified by the actual design and construction of the T&A House in Solar Decathlon China (SDC) competition. The research results show that the BIM-based collaborative design method can facilitate the completion of a construction project and achieve the expected goal of zero energy consumption in ZEBs.

Solar Decathlon is a multi-disciplinary international competition that integrates energy-saving design strategies to design, build and operate zero-energy solar houses. This study focused on the 15 entries in the third Solar Decathlon China. It summarized their energy-saving design strategies into strategies of architectural design, equipment management, energy acquisition and intelligent regulation, and extracted a total of 22 key design elements. Based on the scoring results of the competition, this study analyzed the application of different design strategies with qualitative analysis; through quantitative analysis, 22 design elements were associated with the score, and the impact of different strategies on the score was comprehensively analyzed. As revealed in the data, design concept, functional structure and application type of renewable energy are significantly correlated with and have a great impact on the score; in contrast, building area and thermal buffer space are not significantly correlated with the score. On the basis of data analysis, this study provides a quantitative decision basis for the energy-saving design strategy of zero-energy buildings, and establishes an empirical model for the design of zero-energy solar buildings in Zhangbei County, Zhangjiakou City. This paper is helpful for the design practice and application of subsequent studies on ZEBs.