The ENTROPY project aspires to significantly contribute to (1) the reduction of energy consumption, and (2) the reduction of micro-generated energy losses, in buildings. As part of this ongoing project, we have created a sensor networking infrastructure for the interconnection of heterogeneous smart sensors and devices, and the aggregation and fusion of data from multiple sources. The developed architecture provides the relevant and necessary data for the further development of energy-efficiency solutions for buildings with the aim to reduce the energy consumption and reduce the micro-generated energy losses. The sensor deployment is presented in this article for the two use cases of the HES-SO pilot. Ongoing work envisages to utilize the deployed infrastructure in conjunction with gamification techniques and serious gaming applications to record, and analyze the energy behavior of residents, and train them in order to adopt more energy efficient behaviors.