Integration of Polymer‐Based Phase Change Materials Into Building Walls in the Hot Region of Algeria

ABSTRACT This study aims to evaluate the effects of incorporating polymer‐based phase change materials (PCMs) on the thermal performance of building walls in the hot region of Algeria. The analysis uses outdoor temperature data from 18 provinces representing this climatic zone. A numerical study is conducted to assess how placing a PCM layer in exterior wall layers influences indoor temperature stability. The results show that adding a PCM layer reduces indoor temperature variations, particularly when placed near the outer face of the wall. Among the tested materials, the PEG (50 wt%)/diatomite composite provides the most significant improvement, keeping indoor temperatures within the 20°C–27°C comfort range for about 35% of the time compared to the reference wall. PEG (50 wt%)/diatomite with the lowest melting temperature shows effectiveness in reducing the temperature fluctuation during summer conditions. Using fatty‐acid polyurethane in the optimal configuration increases the comfort range to 31%, while PEG‐1000 improves indoor comfort by 6% compared with the reference wall. These findings indicate that using polymer‐based PCMs in external walls enhances energy performance and thermal comfort in Algeria's hot climate.