[EN] This work presents a comparative study between two buildings or cubicles with a same geometry and orientation but with different constructive layers. The mineral wool cubicle is more insulated whereas the alveolar cubicle has more thermal inertia. A novel point in this study has been to evaluate indirectly the thermal load based on the energy consumption of the heat pumps. The results indicate that the mineral wool cubicle consumes up to 7.3% less energy consumption than the alveolar cubicle, particularly in summer. In fact, the load in summer is up to 11.6% higher with the alveolar cubicle, which gains more solar energy during daytime due to its inertia. The power consumption is practically aligned with the outdoor temperatures since it is very sensitive to the operating temperatures. Nevertheless, the peak building load can take place up to 5 hours later than the peak outdoor temperature, particularly in summer and in the alveolar cubicle. Finally, the proposed approach has helped obtained in-situ U-values of 0.20-0.27 W m−2 K−1 for both cubicles. The work partially funded by the Spanish government (ULLE10-4E-1305). The authors from Lleida would like to thank the Catalan Government for the quality accreditation given to their research group (2014 SGR 123). The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) under grant agreement No. PIRSES-GA-2013-610692 (INNOSTORAGE). This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 657466 (INPATH-TES). Alvaro de Gracia would like to thank the Education Ministry of Chile for Grant PMI ANTI 201.