Why Do You Need An EPC? When a property is to be advertised for sale or rent, it will legally require an Energy Performance Certificate (EPC). Estate agents and property websites are unable to advertise a property for sale or rent without a valid EPC. ? What is it exactly? An EPC is a report of a property’s energy rating, based on the use of heating, water heating and lighting. The report will give the property an energy rating from \'A\' (100) to ‘G’ (1) depending on how energy efficient the property is. In addition to the rating, the EPC gives an estimation of fuel running costs and recommendations to improve the rating, along with the estimated costs of installing any recommended measures.