EPCS FOR EXISTING BUILDINGS

This document shows two ratings, both of which are derived from RDSAP – a reduced data version of the full assessment used for existing homes. The headline score is the estimated fuel cost rating, expressed as a mark from A to F, depending on the band the SAP score (one to 100) falls into. The other rating shown on the certificate is the Environmental Impact Rating (EIR), which comes on the last page of the report and details the estimated annual CO2 emissions of the property.

Remember that the EPC rating is an estimation of fuel cost – not an evaluation of energy performance. It also has the bizarre result that you could switch from biomass heating, which is low carbon, to oil, which is high carbon. By doing so, you could improve your EPC rating, simply because oil is currently cheaper than biomass according to the RDSAP.