BACS Requirements in Ireland

Article 13 of Directive (EU) 2024/1275 mandates BACS in non-residential buildings where technically and economically feasible.

In Ireland, building energy performance is governed by Building Regulations Part L (Conservation of Fuel and Energy) and the European Union (Energy Performance of Buildings) Regulations. The Sustainable Energy Authority of Ireland (SEAI) administers the BER (Building Energy Rating) system and energy efficiency programs.

The technical standard is EN ISO 52120-1 (formerly EN 15232). Class C is the minimum acceptable BACS level.

The mandate targets non-residential buildings — offices, retail, hotels, hospitals, schools, and logistics or industrial sites with significant HVAC load. Scope is set by the effective rated output of the technical systems: the combined capacity of heating, ventilation, air-conditioning, and hot-water plant. A building with a 120 kW heating system and a 60 kW cooling system reaches 180 kW, well inside the 70 kW threshold and so in scope for 2029.

Residential buildings are excluded, and mixed-use buildings are assessed on their non-residential portion. Ireland's commercial stock — much of it built during the 2000s expansion — includes a large share of offices and retail running on controls below EN ISO 52120-1 Class C, which is where the upgrade demand concentrates.

Reaching Class C is about capability, not just hardware. A compliant system must continuously monitor energy use, benchmark it against expected performance, detect faults and efficiency drift, give operators actionable information, and control HVAC to actual demand rather than fixed schedules. Timer circuits and standalone thermostats do not qualify.

For Irish building owners, a BACS upgrade also supports a better BER rating and the Climate Action Plan emissions trajectory, so the compliance project and the decarbonisation case tend to align. The practical first question is whether the existing BMS can already monitor, report, and optimise — or whether it only switches plant on and off.

• SEAI (Sustainable Energy Authority of Ireland) administers the BER system and energy efficiency grant programs for commercial buildings.
• EXEED (Excellence in Energy Efficient Design) certification already encourages advanced building controls in new-build and retrofit projects.
• Support Scheme for Energy Audits (SSEA) provides co-funding for energy audits that can identify BACS upgrade opportunities.
• Climate Action Plan 2024 targets a 50% reduction in commercial building emissions by 2030, making BACS upgrades a key enabler.
• Part L of Building Regulations sets minimum energy performance standards. Updates to reflect EPBD 2024 recast are expected.