The efficient energy management of buildings is nowadays a crucial point to move toward a sustainable planet. Unfortunately, the design of smart buildings able to optimize their energy consumption is a quite complex task. Since this exploration cannot be performed on the field, simulation methodologies are usually adopted to study the behavior of buildings and their energy sustainability during the design phase. This paper proposes a simulation framework based on SystemC to easily evaluate different policies to control the energy consumption of a smart space. In particular, SystemC makes it possible to obtain a flexible representation of the system, allowing the designer to easily evaluate different configurations of appliances and policies, and it directly works with the commonly-used C programming language.