A weighted multi-objective optimisation approach to improve based facade aperture sizes in terms of energy, thermal comfort and daylight usage

In building design, the decision-makers should not focus only on energy efficiency as a single objective but indoor environmental quality indicators, such as thermal comfort, daylight usage and so on, should also be considered as a part of building performance. The building performance can be ensured by determining the proper performance indicators and the variables during the design. In this context, a weighted (among the objectives) multi-objective cost function was proposed, for the optimisation of energy, thermal comfort and daylight usage of a case study archetype design, through the selected design variables, considering the base architectural design principles as well. A typical social housing archetype design was determined as the case study to apply the proposed approach. The window sizes are optimised for each orientation simultaneously, for a temperate-humid climatic region. The results were evaluated in terms of improvement potentials of energy, thermal comfort and daylight performances, and the dominant values for the window sizes for each facade. According to the results, the optimised scenario achieved an 11.42% reduction in primary energy use equivalent to 181.24 kWh/m²a, a 4.52% reduction in a predicted percentage of dissatisfied with 9.12%, and a reduction in lighting energy of 4.94% equivalent to 21.17 kWh/m²a. These reductions verify the possibility to achieve higher performances on each criterion.