The world is increasingly experiencing a strong need for energy consumption reduction and a need for efficient use of scarce natural resources. Official studies report that buildings account for the largest portion of the world’s energy expenditure and have the fastest growth rate. Clearly, energy saving strategies that target energy use in buildings and surroundings can have a major impact worldwide, driving the current energy market toward self-sufficiency and self-sustainability. This calls for effective techniques and methods that enable accurate carbon foot printing, monitoring and control of appliance activity, energy auditing and management in buildings and surroundings and the generation of energy awareness. Wireless sensor networks (WSNs) play a key role in enabling energy-saving systems in buildings and surrounding spaces by providing a reliable, cost-effective and extensible solution that can be placed in essential tool in the control loop that will be used in future structures for the generation and usage of diverse types of energy. BuildSys is a venue for incubating new directions in this area.