The updated EPBD introduces several new elements, such as the calculation of EP-values based on total primary energy rather than non-renewable primary energy, marking a significant shift. Determining EP-values according to the revised EPBD and establishing corresponding thresholds for energy and operational CO2 emissions in zero-emission buildings pose important questions for energy experts across all Member States tasked with implementing the directive. 

REHVA experts have developed a methodology, inclusive of assessment boundaries and calculation guidelines, accompanied by practical examples for primary energy and CO2 indicators, to facilitate consistent adoption of the EPBD. This ensures adherence to the 'energy efficiency first' principle, emphasising the minimisation of energy consumption from both renewable and non-renewable sources through efficiency measures.