Thermal and Energetic Contributions of PCM Plaster According to its Location and Type of Masonry—Experimental and Numerical Studies in a City With a Temperate Mediterranean Climate

The integration of phase change materials (PCMs) in the construction sector is very promising for the improvement of the thermal and energy performance of buildings. This multi-variable study aims to reveal the contribution of PCM plaster according to the type of masonry (single cement bricks or double clay bricks), the type of plaster (PCM or cement plaster) and its location (interior or exterior) to reduce indoor temperature fluctuations and energy consumption levels. Small-scale experimentation and dwelling dynamic modelling of several types of rooms have revealed that compared to cement plaster, PCM plaster on the interior surface of exposed walls reduces the indoor temperature fluctuation range by up to 2.5°C on winter days and by up to 2.6°C on summer days if it is applied on the exterior surface of the single-partition walls. In the case of double-partition walls, the reduction in the indoor temperature fluctuation range reaches 1°C on winter days and 1.3°C on summer days. Interior PCM plaster reduces the heating energy demand in winter by up to 25% for single partitions and 21% for double partitions. In summer, the reduction in cooling energy demand with exterior PCM plaster is up to 36% for single walls and 44% for double walls. Compared to cement plaster, although the thermal and energy reduction percentages of PCM plaster are greater for single-partition walls, the temperature fluctuations and energy consumption are lower for double-partition walls. Determination of the optimum melting temperature and thickness of PCM plaster would improve the performance obtained.