Energy Performance Optimisation of Low-Rise Lightweight Steel-Frame Houses by Evolutionary Approach

China is in the process of expanding its stock of low-rise LSF buildings in suburban and rural areas. This construction system is underused compared with most developed countries, but the number of low-rise steel-framed residential buildings is projected to increase due to the current national policies promoting rural green steel-framed houses. The building envelope is the most influential design factor in energy performance, and to better understand the effects of design decisions, this article investigates its optimisation by jEPlus + EA (EnergyPlus simulation manager for parametric + Evolutionary Algorithms). The objective functions are to minimise heating and cooling needs. The variables describe the main envelope components of a low-rise lightweight steel-frame house. The results confirm a significant potential for energy saving in comparison to different benchmark specifications and demonstrate the effectiveness of the method tested in the study.