Building automation and control systems (BACS)

About building automation and control systems (BACS)

Reducing the energy consumption of a building is directly related to the building managers ability to record and monitor their usage. The optimisation of a building's energy usage cannot be maximised without having a way to monitor and record when, where and how much energy is being used within the building.

The quickest and most cost-effective gains for any building are those resulting from a monitoring and automated control-based approach to improving energy management. Building automation and control systems (BACS) provide this capability.

The complexity of these systems can be varied but should provide the ability to centrally monitor and record energy usage and schedule the automatic operation of building systems based on appropriate parameters such as time or space temperatures.

Buildings that must comply

The European Union (Energy Performance of Buildings) Regulations 2021 (S.I. 393 of 2021) is introducing a requirement for building owners to install Building Automation and control Systems (BACS) in buildings where the effective rated output of heating, air-conditioning and ventilation system(s) in a building is above a threshold of 290 kW must follow these regulations by 31st December 2024.

All buildings who have an obligation based on the outlined parameters must have these systems installed by the deadline, 31st December 2024.

There is potential exemption if installation of the required BACS is deemed not technically or economically feasible based on independent assessment.

Drivers and benefits of the Regulations

The basis of these regulations is centred around harnessing the opportunities within all buildings where there is a lack of visibility around what energy is being used and where it is going. Through the use of current available technologies, the practicality for existing buildings to install such systems has never been more achievable.

Typical benefits of this intervention include:

• Limited disruption to buildings and operations
• High cost to savings ratio
• Ability to identify high energy uses
• Ongoing identification of malfunctioning equipment and controls
• Allowing for data-based prioritisation of other projects
• An attractive selling point to tenants
• Evidence to access Green Finance

How to assess your building

The buildings heating, air-conditioning and ventilation systems should be reviewed to determine the size of the systems.

Automation and control systems are required to be installed in accordance with the functionality outlined in Paragraphs 1.1.1 and 1.1.2 of the Energy Performance of Buildings Regulations 2021 Technical Guidance, where technically and economically feasible.

Steps needed to reach compliance

1. Where the combined systems are larger than 290 kW, a building will need to comply. (Refer to our BACS Requirements Factsheets for sample calculations and other relevant info.)
2. If the Regulations apply, assess if a building automation and control system is in place and if it meets the requirements of Paragraphs 1.1.1 and 1.1.2 of the EPB Regulations 2021 Technical Guidance.
3. Install the required Building Automation and Control system by 31st December 2024 if it is technically and economically feasible.
4. If installation of the required BACS is deemed not technically or economically feasible, this should be confirmed by an independant, competent professional, following their assessment on the technical and economic feasibility of installing a Building Automation and Control system in the building.

SEAI factsheets on understanding BACS requirements

• BACS Compliance Assessment
• BACS Leased Buildings Requirements
• BACS Leisure Centres Requirements
• BACS Manufacturing Building Requirements
• BACS Public Sector Requirements