The objective of this paper was to present an integrated system for buildings’ energy-efficient automation customized to the users’ requirement and building characteristics. The presented system was based on a prototype software tool. In particular, the combination of the proposed system with the optional installation and operation of an automation system of sensors and meters are a step forward for the simulation and optimization of energy consumption in the building sector. The contribution of the proposed system to the related scientific literature on the energy and environmental management of the building sector is summarized as follows: