Analysis of Thermal Performance of Phase Change Materials (PCMs) in Building Wall Systems for Energy Efficiency

Phase Change Materials (PCMs) have emerged as an effective solution for enhancing thermal energy storage and improving the energy efficiency of building envelopes in both residential and commercial structures. This study investigates the thermal performance of PCMs when integrated into building wall systems under varying climatic conditions. Experimental wall prototypes incorporating paraffin-based PCMs were subjected to controlled heat flux to evaluate thermal lag, peak temperature reduction, and energy-saving potential. The results showed that PCM-enhanced walls significantly reduced indoor temperature fluctuations, lowering peak temperatures by 4–7°C compared to conventional brick walls. The thermal storage capacity of the PCM layer increased the time delay of heat transfer by up to 2.5 hours, contributing to improved indoor comfort and decreased cooling load demand. The findings demonstrate that PCM integration in building envelopes offers a promising passive method for increasing building energy efficiency, especially in regions with high diurnal temperature variations.