Overview
SIST EN ISO 16484-4:2025 - Building automation and control systems (BACS) Part 4: Control applications defines standardised control applications and function blocks used in building automation. The standard focuses on translating building energy performance, comfort, and operational requirements into consistent functional specifications for integrated room and plant control. It covers lighting, solar protection (blinds), heating, ventilation, air conditioning (HVAC), domestic hot water (DHW), thermal energy storage (TES), and related sensor/actuator functions. EN ISO 16484-4:2025 supersedes EN 17609:2022 and has been adopted by CEN members.
Key topics and technical scope
- Control applications and sequences for: heating, cooling, ventilation, DHW, lighting and blind control.
- Function blocks and modular control elements (sensor functions, actuator functions, display/user operation).
- Specific technical areas included:
- Emission and distribution control for heating and cooling (including TABS and hydronic balancing)
- Generator sequencing (heat pumps, boilers, chillers) and TES charging
- Ventilation control (supply air, outside air, heat recovery, humidity, free cooling)
- Lighting control (occupancy, daylight harvesting) and blind/solar protection strategies (manual/automatic/combined)
- Sensor definitions (temperature, humidity, brightness, presence, flow, dewpoint, etc.) and actuator behaviours
- Emphasis on functional specifications that impact energy efficiency, occupant comfort and operational reliability.
- Structured content enabling interoperability and consistent implementation across BACS vendors.
Practical applications
- Translate performance and comfort requirements into implementable control logic for building management systems (BMS/BACS).
- Develop standardised control sequences and function blocks for energy-optimised HVAC, lighting and shading control.
- Inform commissioning, testing and validation procedures for integrated room and plant controls.
- Support specification writing for tenders, procurement and product development to ensure interoperability.
- Guide implementation of daylight harvesting, occupancy-based lighting, heat/cool sequencing, TES integration and hydronic balancing.
Who should use this standard
- Building services engineers and HVAC designers
- BMS / BACS system integrators and software developers
- Facilities managers and energy managers seeking operational efficiency
- Lighting and solar protection (blind) control specialists
- Manufacturers of controllers, sensors and actuators
- Consultants, specifiers and authorities referencing harmonised building automation requirements
Related standards and notes
- Part of the ISO 16484 series for BACS - intended to be used alongside other parts of ISO 16484 and national CEN-adopted standards.
- Adopted as EN ISO 16484-4:2025 - check national standard bodies for implementation details and normative references.
Keywords: Building automation and control systems, BACS, ISO 16484-4:2025, control applications, HVAC control, lighting control, solar protection, function blocks, energy performance, building management systems.
