Abstract
The increased energy consumption in residential buildings has recently received significant concern, especially regarding the thermal performance of buildings and the building's resilience towards climate change. Reducing energy consumption resulting from the heating and cooling demands of a building and limiting heat loss or gain can play a major role in buildings' energy saving. Thermal insulation of building walls has a significant impact on energy saving. This study investigated certain types of walls to achieve the best thermal performance for the external walls of residential buildings. These models are enhanced with selected insulation materials and have been thermally examined in extreme conditions in the Mediterranean region. The impact of the used materials on the thermal performance of building envelopes was assessed, then validated using FLUENT software based on the location of the insulation layer, thickness, and thermal behaviour. The study showed that using Phase Change Material (PCM) insulation materials in the wall composition has a significant impact on the thermal performance of the building envelope, heat transfer, and temperature distribution. The heat transfer calculations showed that the average temperature of the internal surface of the wall can be decreased by almost (1.5-3.5) °C in the summer and increased by almost (2-6.5) °C in winter when applying Paraffin of 2 cm of thickness and located in the middle of wall composition within extreme climatic conditions compared to the system with no insulation.