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A heating floor is a low‐temperature emitter consisting of pipelines in which a fluid circulates between 35°C and 45°C. To ensure energy efficiency, occupant comfort, and building material durability, proper heat management is crucial in buildings. By using phase change materials (PCMs) in building envelopes, the indoor temperature can be regulated through the storage and release of thermal energy, which reduces energy consumption and enhances occupant comfort. In this study, we evaluated numerically a heating floor that incorporates a PCM enhanced by nanoparticles (NePCM). The aim of the numerical analysis is to assess the impact of the addition of single and hybrid nanoparticles in different proportions to the PCM layer on the thermal performance of the PCM‐based floor. Therefore, two main objectives are defined. The primary is to take advantage of the storage capacity of a PCM layer by integrating it into the ground; second, to evaluate the hot water temperature levels effect on the floor's performance. Additionally, we address the low thermal conductivity of PCM by enhancing PCM microcapsules with single and hybrid nanoparticles and comparing them to pure PCM. The numerical results obtained show that positioning the PCM microcapsules above the heating tubes (upper position) provides an optimum improvement in thermal performance. Moreover, the addition of hybrid nanoparticles within the base PCM, 1% of Cu mixed with 4% of Al2O3, allows an increase of 4°C, which relates to a reduction of 18% in the internal temperature amplitude and a phase shift of 6 h 30 min compared with the conventional heated floor in which there is no PCM.

A phase change material (PCM) allows releasing and absorbing energy at the phase change transition. They are employed in building walls to maintain internal thermal comfort and optimize thermal energy storage.However, the hottest cities in Morocco suffer from overheating during peak days. Consequently in this article, the purpose is to evaluate the thermal performance of incorporation of the PCM n-octadecane paraffin in a typical multilayer wall at three different locations for a Moroccan hot climate zone. Numerical simulation is developed in a two-dimensional transient in addition to mathematical modeling using the enthalpy-porosity approach for three wall types. An implicit finite volume method is used for the numerical solution. The effects of PCM location, PCM type, and mass fraction (varying between 15% and 35%) are studied and compared with the reference case (without PCM). The evaluation of mass fraction variation is based on two determining factors of the wall panel's thermal inertia: the time delay and amplitude attenuation. The surface heat fluxes will then be used to quantify the capacity of the multilayer wall to store and release energy. The results showed that to ensure the thermal performance of the wall, it is useless to exceed 20% of mass fraction for all types of multilayer walls.

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