Multi-optimization Evaluation for the Building Envelope to Enhance Efficiency and Sustainability

The thermal transmittance (U-value) of the building envelope and the climatic conditions are the determining factors in the determination of energy efficiency and building performance. This study systematically examines the impact of the synergy between the reflective properties and thermal resistance of the opaque portion of the building envelope. The NSGA-II multi-optimization was employed to analyze the synergy between U-values and reflective coating. The outcomes were contrasted significantly for with and without reflective coating on the building roof. The energy-saving analysis was conducted for three distinct scenarios, each of which was based on the building’s operational duration. The most optimal solution yielded an energy savings of up to 26.3%, as determined by the heating and cooling multi-objective optimization. Nevertheless, the demand for heating energy experiences a substantial increase; however, its overall impact is negligible as a result of the location's shorter heating duration. In order to optimize energy performance, the optimal U-value for walling and roofing systems is 0.5 W/m2K. Nevertheless, the application of reflective paint to the roof necessitates a U value of 1.5 W/m2K or higher.