1. A computer-implemented system for facilitating communication between a plurality of building automation subsystems and a plurality of applications, comprising: a first database storing a hierarchical model of a building automation system; a second database storing information for the plurality of building automation subsystems, wherein the second database stores each record with a projected semantic type string comprising multiple levels of type information and based on the hierarchical model stored in the first database; and a messaging engine configured to receive a message from one of the disparate building automation subsystems and for one of the plurality of applications, wherein the messaging engine is configured to use the information in the second database to transform the message into a standard format, to append the projected semantic type string to the transformed message, and to provide the transformed message to one of the plurality of applications.