BACnet models the data of building automation components as objects. Those include Analog, Binary and Multi-State Input, Output and Value Objects, primitive data, the representation of devices, counters, calendar and scheduling, trend-logging, alarming, life-safety and access control objects as well as objects to represent a building structure (groups, structured views).

Objects consist of properties to represent the data associated to the specific information. This includes text information like the name and description, the technical address of the data, the present value, units, alarm-limits as well as specific building automation functionality like command priorities, elapsed active time or change-of-state counting. Due to the de-central approach of BACnet a client can request all information from a device representing data as a server.