Integrating window drives into building management systems

Updated: 08.11.2026

In larger buildings with many windows, skylights, or facade vents, an isolated drive control system quickly becomes insufficient. To ensure that architects, electrical engineers, and facility managers maintain an overview, window drives must be seamlessly integrated into the central building management system (BMS).

In brief: In larger buildings, window actuators are connected to the building management system so they can be monitored and controlled centrally. Typical bus systems are KNX, Modbus and BACnet, and the interface should be fixed early in the project. The smart i-series actuators from Vent Systems have a Modbus interface.

Why window drives are connected to the building management system

A connection to the building management system (BMS) enables centralized monitoring and remote control of all drives from one location, unified alarm and fault management, and interaction with heating, ventilation, and air conditioning systems – for example, for automated night cooling via open window drives. Especially when Smoke and heat exhaust ventilation systems A clean connection is also relevant for safety, as status messages from the drives must be traceable at all times.

Which interfaces are suitable?

Several bus systems have become established in building automation, allowing window drives to be connected to the building management system (BMS) – including KNX, Modbus, and BACnet. The system used usually depends on the existing building automation system and the electrical planner's specifications. It is important to define the interface early in the project so that the appropriate drives can be planned from the outset.

Synchronization of multiple window drives

As soon as multiple drives on a single window or several windows on a facade need to open together, a simple on/off control is no longer sufficient: If the drives don't run exactly synchronously, sashes and skylights can become misaligned or wear unevenly. A synchronization function ensures that multiple drives work together at identical speed and position. Our VS-LA-i smart linear actuator This function is already included as standard and can be directly integrated into bus systems.

What needs to be considered when planning integration

• Coordinate the interface and bus system early on between facade, electrical and building automation planning.
• Define clear feedback signals – status open/closed, fault, maintenance requirement
• In combined systems: Smoke and heat exhaust ventilation (SHEV) activation in case of fire must always take priority over everyday building management system (BMS) control.
• Clarify the drive type and synchronization requirements together with the manufacturer before finalizing the electrical planning.

For individual rooms without a connection to the building management system, a local solution with a button, control unit and rain sensor is often sufficient – more on this in the article. Ventilation control for window actuators.

How to connect 24 V and 230 V chain actuators correctly is explained in the guide Connecting a chain actuator.

Read more: Integrating a window drive into a smart home: Home Assistant, Loxone, Homematic

Frequently asked questions

Can I integrate a window actuator into KNX or a smart home?

Our control units do not have a KNX interface. However, 230 V actuators can be integrated via a KNX actuator that opens and closes them much like a blind motor. For 24 V actuators, we clarify the connection case by case with your electrical planner.

Does the actuator report whether the window is closed?

Simple actuators do not report their position. Some of our actuators have position feedback, so the control unit can tell whether the window is open or closed. Ask us via the Contact formwhich of them suit your window.

Do the actuators work with Home Assistant or Loxone?

The smart i-series actuators (VS-KA-i, VS-LA-i, VS-ZA-i, VS-SB 400-i) have a Modbus-Schnittstelle. Smart-Home-Systeme, die Modbus unterstützen, können sie darüber ansteuern; je nach System ist dafür ein Modbus-Adapter nötig. Standard-24-V-Antriebe lassen sich über eine Lüftungssteuerung mit Tastereingang oder über Relais für Auf und Zu einbinden. Welche Lösung zu Ihrem System passt, klären wir vor dem Kauf.

Conclusion

Window drives that integrate seamlessly into building management systems save operating costs and simultaneously increase the safety of smoke and heat exhaust ventilation systems. Considering the appropriate interface and synchronization function during the planning phase prevents later retrofitting. We would be happy to advise you on which drive solution is best suited for your building management system project.