The objective of this work is to numerically investigate the thermal analysis of typical United Arab Emirates (UAE) bricks containing an organic phase change material (PCM) under the UAE's hot climate. Latent heat of fusion was used to reduce the heat loads fluctuation and peak time shifting. That, in turn, reduces the consumed energy for cooling and therefore reduces the green gas emissions. A one day versus a seven days analysis was performed and compared to account for the cyclic behavior of the PCM in the building material. The study focuses on demonstrating the deceiving results which can be concluded from each analysis. The results demonstrate that choosing the proper PCM material for this application is tricky and required at least a seven day analysis evaluation. A One day evaluation can be misleading, where its results suggest that using the n-Octadecane PCM with a melting temperature of 27 degrees C provides the best energy saving for this application. Meanwhile, based on a seven day analysis the PCM P116 with a melting temperature of 47 degrees C demonstrated the best performance. (C) 2017 Elsevier B.V. All rights reserved.