Actual power systems are evolving towards the Smart Grid concept. Being buildings part of the grid, and considering their distributed generation and controllable demand capabilities, they are becoming key players in the framework of liberalized electricity markets. New integrated smart homes and buildings will contribute to the protection of the earth environment while reducing their operational costs. They will take into account not only technical issues of their integrated sub-systems but also users requirements. In order to fulfil these goals an accurate building model could be considered using a standard-based communication infrastructure, linking all buildings elements (physical and human) and allowing buildings to become an active part of the smart grid itself.