Potential of glazing facades with shading devices for energy savings and occupant comfort in office buildings in hot-humid climates

摘要

The number of office buildings in Southeast Asia is predicted to increase as a result of economic growth. The buildings' glazing facades are subject to considerable heat gain from daylight via incident solar radiation. However, users' interaction with internal blinds plays an important role in building-facade performance. Therefore, this study aimed to clarify the impact of glazing facades with internal blinds on occupants' comfort and the energy used under a post-occupancy situation. On-site measurement was completed in four Thai office buildings during working hours. Measuring devices were installed to investigate the optical properties of the building facades and indoor environment. The sensation and satisfaction from the 1,138 samples were simultaneously investigated via questionnaires. The results show that the high occlusion of internal blinds results in low solar heat gain coefficients and visible light transmittance rates. The transmitted solar effect has less of an impact on the indoor environment. Most of the occupants are satisfied. Moreover, both thermal and visual comfort can be recognized as a significant correlation. In addition, lowering internal blinds is an important factor in increasing building energy efficiency, particularly for low thermal-performance glazing. Thus, it was demonstrated that internal blinds are required to create a comfortable indoor environment with higher energy efficiency in Southeast Asian office buildings. Optimization of building facades is necessary to improve shading devices as an effective layer.