PHASE CHANGE MATERIALS (PCM) IN THE BUILDING ENVELOPE: STATE OF THE ART

Faced with the increasing energy demand linked to air conditioning in hot and humid climate countries, phase change materials (PCM) represent a promising passive solution to improve the thermal performance of the building envelope. This article presents a structured review in six parts. First, the physicochemical mechanisms governing the storage and release of energy by latent heat are explained. A multi-criteria classification of PCMs is then proposed, according to their chemical composition, microstructure and phase transition temperature. Selection factors such as thermal, physical and chemical properties are analyzed in order to identify the determining criteria for effective integration. The article then examines the different methods of integrating PCMs into building components such as vertical walls, ceilings, floors and glazing, drawing on documented experimental results showing significant reductions in interior peak temperatures and thermal oscillations. The impacts on load-bearing materials are also assessed: although the incorporation of micro-encapsulated PCMs improves thermal inertia, it leads to a degradation of mechanical properties and a significant increase in porosity, proportional to the incorporation rate. Finally, environmental and economic assessments reveal that bio-sourced PCMs have a significantly lower carbon footprint than conventional paraffins, while profitability remains strongly dependent on the climatic context and the type of application. This review aims to provide a documented basis to guide future work on adapting PCMs to the constructive and climatic specificities of West Africa.