In order to limit the exorbitant energy consumption by the use of mechanical heating and cooling systems, several buildings are trying to adopt a heat storage
system as a part of the energy system of the building. However, there are also passive systems that perform independently from the building’s energy system and store heat in alternative ways. More specifically, an efficient way to achieve thermal energy storage is the use of phase change materials (PCMs) in the building construction. PCMs offer a high thermal storage density with a moderate temperature variation, and have attracted growing attention due to their important role in achieving energy conservation in lightweight buildings while maintaining thermal comfort. Research in this area has resulted in findings, which depict a significant plummet in temperature variations whilst maintaining desirable thermal comfort. Despite these findings, only a few research projects deal with the implementation of PCMs in the façade system,
as a method to enhance the visual and the thermal comfort of the indoor environment of the buildings. This paper summarises previous works on latent thermal energy storage in building applications, covering PCMs, the current building applications and their thermal performance. It also provides new innovative ideas on integrating PCM in the building envelope, as well as on their impact on the visual and the thermal quality of the indoor space.