Electric vehicles and plug-in hybrids are gaining popularity on the personal transportation market. These vehicles store energy that is unused when parked. This distributed energy source can therefore be used to provide ancillary services such as grid regulation or spinning reserves, but also for demand-side management. In this paper, we are proposing the concept of collaborative charging in the context of Vehicle-to-Building, where the vehicle and building operators engage themselves into a synergistic relation, with vehicles freely charged in exchange for shaving power peaks of buildings. For that purpose, simulations of vehicle fleets are conducted, with the charging schedule optimized by a linear programming model that is applied to manage the electric demand of a suburban university campus. These simulations, made in the context of a regulated electric market, demonstrate that collaborative charging can be financially viable for both the institution hosting the system and the participants.