To generate the required EPC files for the pre and post refurbishment building, the same software and software version should be used.
In cases where there is an existing EPC using a different software or a different software version, it would therefore be necessary to generate a new EPC for the existing building, using the same software that is being used to model the refurbished building performance.
In addition, to maintain consistency, where possible the energy modelling should be carried out by the same energy assessor.
This is to avoid differences in performance resulting from changes to the calculation software, rather than changes to the building or other inconsistency.
