Abstract This study aims at developing a new integrated component in a passive solar wall to achieve high thermal energy storage potential in building materials. This component was manufactured by conditioning the paraffin inside 24 copper tubes, which were regularly inserted and aligned in a gypsum matrix. Firstly, an investigation by means of a differential scanning calorimeter (DSC) was carried out to obtain the latent heat and the transition temperature of the selected phase change material (paraffin). Secondly, an additional study was conducted to gauge the improvement of energy storage performance in classical construction material (gypsum) when incorporating paraffin by the method of transient guarded hot plates. The results of this experiment revealed a clear improvement in different thermal properties when integrating paraffin in the composite. Besides, the results showed that the composite-PCM prevents the leakage of the molten paraffin during phase transition and proved a good thermal stability.