Office buildings are characterized by high operational costs and high emission levels. Growing needs of energy saving in office buildings have driven increasing interest in developing approaches that can plan the demand of buildings intelligently. In this paper we propose an approach for demand-side management based on AI planning so that energy efficiency and occupants’ experience in office buildings equipped with IoT devices can be improved. Thanks to AI planning, we are able to model the domain of a building coordination problem in Planning Domain Definition Language (PDDL) and find the effective schedules of device actions.