Energy consumption trends in residential and commercial buildings show a significant increase in recent decades. One of the key points for reducing energy consumption in buildings is to decrease the energy demand. Buildings envelopes are not just a structure they also provide protection from outdoor weather conditions always taking into account the local climate. Thermal energy storage has been used and applied to the building structure by taking advantage of sensible heat storage of materials with high thermal mass. But in recent years, researchers have focused their studies on the implementation of latent heat storage materials that if well incorporated could have high potential in energy demand reduction without occupying the space required by sensible storage. The aim of this study is to review the thermal energy storage passive systems that have been integrated in building components such as walls, ceilings or floors, and to classify them depending on their component integration. ; The work was carried out under the framework of the COST Action BISTS TU1205. The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007–2013) under grant agreement n° PIRSES-GA-2013-610692 (INNOSTORAGE). The authors from the University of Lleida would like to thank the Catalan Government for the quality accreditation given to their research group (2014 SGR 123). Alvaro de Gracia would like to thank Education Ministry of Chile for Grant PMI ANT1201.