A building control system comprises a central control station and at least one control panel connected to the central control station over a network. At least one loop is connected to at least one control panel. The at least one loop comprises a plurality of installed building control devices connected in an electrical circuit. A simulator is also connected to the network and configured to simulate the operation of a plurality of uninstalled building control devices for the building control system. The simulator is further configured to communicate over the network with the plurality of installed building control devices. Simulation of the operation of the uninstalled building control devices occurs simultaneously with the communication between the installed building control devices and the simulator. Accordingly, the simulator may be used to test the entire building control system during the process of installation at a facility.