Özet:
In this study, the effect of phase change material on walls and roof considering solar intensity was discussed. Due to the geographical location of the city of Jeddah in Saudi Arabia, the effect of installing phase change material within thicknesses of 1–10 cm in the period from April 1 to September 30 was investigated. Numerical results showed that if phase change material is added to the roof (at 1 cm), the heat transfer not only did not decline but also increased. However, for the walls in the main directions, phase change material (at 1 cm) was useful. Based on the results, the western wall was the most sensitive wall to phase change material presence so that the addition of phase change material at 1–5 cm resulted in energy-saving by 2.4–7.2 kWh/m2. Although phase change material at a thickness of 1 was not useful for the roof, at thicknesses of 2–5 cm, the presence of phase change material reduced the energy exchange by 1.21–33.8 kWh/m2. Finally, it was found the best results are obtained by adding phase change material for the western wall and roof. Examining the energy-saving for building by adding phase change material, it was found that adding phase change material with thickness up to 5 cm is recommended. Further increase in thickness reduces the positive effects of phase change material.