Review of thermal and environmental performance of prefabricated buildings: Implications to emission reductions in China

Prefabricated buildings recently became more prominent providing significant benefits including contribution to emission reductions at scale and the manufacturing of building components to high accuracy. However, in China, the proportion of prefabrication is lower than that in many developed countries. The prefabricated wall is one of the most important precast elements and its thermal performance has significant impacts on buildings' energy consumption and environmental performance. This work reviews the thermal performance of prefabricated walls encompassing survey of two common structures, precast concrete sandwich walls and lightweight steel-framed walls. The applicability and limitations of methods frequently used to determine the thermal resistances of these two walls are presented. This article also shows a literature review on the implications of prefabricated buildings to China's emission reductions. Compared to conventional buildings, the contribution of prefabricated buildings on China's emission reduction has been recognized. The potentials on building energy efficient and waste minimisation were also acknowledged. It is concluded that the prefabrication has been generally considered to be a more sustainable method in building sector. The energy-saving potential of prefabrication was demonstrated based on life cycle analysis and thermal performance evaluation. It was found the thermal performance of buildings has multiplied by adopting prefabricated façade elements for building retrofitting. More studies related to thermal performance of prefabricated walls with different structures shall be covered in future research. It is also suggested to develop a more representative result of energy performance by adopting prefabrication, with all dimensions of prefabricated buildings' feature considered.