Explore Cisco
How to Buy

Have an account?

  •   Personalized content
  •   Your products and support

Need an account?

Create an account

What Is Building Automation?

Building automation is the use of automation and control systems to monitor and control buildingwide systems, such as HVAC, lighting, alarms, and security access and cameras. Converging these systems into a single IT-managed network infrastructure creates a smart building. Smart buildings often use Power over Ethernet (PoE) to power and connect IoT devices and sensors.

How does building automation work?

Building automation use sensors and controls to monitor and adjust a building's three types of utilities: electricity, heating and air-conditioning, and water and sewer.

Common examples are:

  • Thermostats to control room temperature
  • Occupancy sensors to control lighting
  • Humidity sensors
  • Fire and smoke detectors
  • Automation of building utilities has evolved at different rates. Typically, each utility system has been controlled separately. More recently, building management systems (BMS)—also known as building automation systems (BAS)—have been developed to help resolve the issue of siloed operations. These systems combine the control of various building automation functions into common control interfaces.

    Using the fourth utility—in this case, a building's data network—smart building systems take building automation to the next level. They do so by not only connecting but also interconnecting sensors and devices to work in coordination, sharing data that helps to manage the building's ecosystem in real time.

    Leveraging building data and applying artificial intelligence and machine learning (AI/ML) to the data makes the building both programmable and responsive to the needs of the users and the building manager.

    Is building automation new?

    Not at all. One of the first notable instances of "building automation" was in the 1880s, when an American professor devised a thermostat to control temperatures in his school classroom. The thermostat concept dates to the 1620s, when a Dutch inventor developed a device to moderate temperatures in an egg incubator.

    Using a building's data network to power and interconnect its operational functions, however, is a recent innovation. The rapid evolution of technologies such as PoE, sensors, and new LED lighting has driven this trend.

    What's the role of PoE in building automation and smart buildings?

    As PoE evolved from delivering 15W to 90W of power across Ethernet cabling, the numbers and types of devices that it can power and connect have grown dramatically. Using PoE to power devices also offers greater location flexibility and lower cost to deploy and operate them than using AC power.

    In a smart building, PoE can power and connect devices that are critical to building automation. Among those devices are sensors and controllers, lighting, heating and cooling systems, elevators, fire alarms, and shades.

    Benefits of building automation

    Lower operational costs

    A smart building automation system can leverage data that it collects to help reduce costs. For example, it can help reduce use of electric lighting by adjusting shades to let in more natural light. Such lighting management has been proved to lower power usage dramatically. 


    Lower energy costs

    Connecting building equipment such as lighting, shades, and HVAC systems enables building operators to automatically adjust temperature, shades, and lighting based on time of day and occupancy. In turn, buildings can become more energy-efficient to meet or exceed stringent regulations for greenhouse-gas emissions.  


    More flexibility to adjust workspaces

    Smart building data can be used, for example, to detect changes in occupancy density. The building's HVAC systems then adjust airflow, humidity, and temperature appropriately.

    Or lighting color could change to indicate too many people in a conference room, workspace, or building when the space's occupancy exceeds density thresholds.

    Building data can also support automated scheduling, from parking-space allocation to workspace assignment to conference room reservation.