In an energy efficient building, a thermostatic controller receives temperature and humidity input signals indicative of an inside, outside and air mass buffer. According to one or more algorithms, the thermostatic controller controls the operations of various actuators, such as blower speed, a fresh air intake vent damper, an exhaust vent and a heat pump, so as to adjust the internal climate of the energy-efficient building towards a control point (e.g., an inside temperature and humidity comfort level).