Devices state changes in a building may be determined using a combination of power monitoring and network monitoring. Power monitoring may be performed by obtaining a power monitoring signal and processing the power monitoring signal with models to determine information about state changes of one or more devices in the building. Network monitoring may be performed by receiving information about network packets transmitted by devices in the building and processing the information about the network packets to determine information about state changes of one or more devices in the building. For some devices and some implementations, information about state changes of a device may be determined by using both power monitoring and network monitoring.