This standard provides a systematic@ comprehensive and modular overall structure on the integrated energy performance of buildings@ in order to ensure consistency among all CEN standards required to calculate the energy performance of buildings according to the EPBD (2010/31/EU). This standard handles the framework of the overall energy performance of a building@ covering inter alia: a) common terms@ definitions and symbols; b) building and system boundaries; c) building partitioning; d) methodology for calculating the energy performance of a building (set of overall formulae on energy used@ delivered@ produced and/or exported at the building site and near-by); e) set of overall formulae and input-output relations@ linking the various elements relevant for the assessment of the overall energy performance of buildings which are treated in separate standards; f) general requirements to standards dealing with partial calculations; g) general rules in setting out alternative calculation routes according to the calculation scope and requirements; h) rules for the combination of different partitioning; i) performance indicators; j) methodology for measured energy performance assessment.