Energy-saving solutions in buildings in Vietnam are a great concern for sustainable development nowadays. However, energy-efficient and cost-saving designs based on the integration of Building Information Modeling (BIM) and building energy analysis are still limited. This study aims to provide energy-efficient and cost-saving designs for buildings by performing the cloud-based building energy simulation. Particularly, the analysis of the impact of changing building parameters on energy consumption and energy cost was performed in this study. Considered building parameters includes building orientation, wall construction, window-to-wall ratio (WWR), lighting efficiency, daylighting and occupancy controls, and, heating ventilation, and air conditioning system. The findings of the study can facilitate building designers, building owners or investors can obtain the best solution for designing the buildings. The first contribution of the study, to provide an in-depth analysis of the impact of the building parameters of energy cost and energy consumption. The second contribution is to contribute to the domain knowledge promotion of the digital transformation in the construction industry.