Theoretical Study on the Effect of Parallel Air Chambers Embedded in Rockwool Panels on the Energy Consumption of a Low-Energy High School

In the construction industry, sustainability is evaluated, not only in terms of harmful emissions generated during the operation phase, but also in terms of the embodied emissions belonging to building materials and technical equipment. As a consequence, the implementation of highly efficient building materials has become crucial. The objective of this study is to investigate an insulation system based on parallel air chambers embodied in rockwool panels, and to correlate the implications of its implementation compared to an existing insulation system. The analysis was conducted on the first administrative/public building completed in Romania, according to passive house standards. The study begins with experimental investigations of insulation systems under laboratory conditions. Thus, the influence of air layers on the thermal properties of existing rockwool panels was assessed. On the basis of the experimental results, the theoretical energy demand of the high school building and life cycle analysis are determined using simulation software for both insulation solutions: existing insulation composed of solid rockwool panels, and rockwool panels with embedded air layers. The thickness of the insulating air layers is optimized, and with the help of Rayleigh–Bénard equations for each of the five climate zones that were further determined. Taken together, it is expected to achieve a better insulation system by maintaining constant embedded emissions. In conclusion, assuming a 50-year life cycle for the high school building, the insulation system composed of rockwool with embedded air layers brings about a reduction in the total energy consumption of approximately 9.82%, compared to the case of a standard insulation system based on solid rockwool panels without additional air layers.