An eight-page building simulation. In this work the design of a pilot building located in Padova (Italy) is presented. This building is equipped with a novel type of thermal active slab fed by a reversible heat pump coupled to ground heat exchanger. The design is based on the concept of night time heat-cool storage and variable comfort conditions during daytime. The simulation results show a strongly reduced maximum heating-cooling capacity (peak-shaving) and a better energy performance in comparison with traditional HVAC systems. The simulations have been carried out by means of TRNSYS as for the building and by means of a model called CARM as for the ground field.