An EPC is needed when a property is built, sold or rented. It gives a property a rating from A to G. It is valid for 10 years.
You may be able to find a property’s rating on the UK Government's Find an energy certificate page .
If a property has ever had an EPC rating, or the certificate has expired, you’ll need to book a property assessment to get a new energy performance certificate. The cost of an assessment varies by assessor and the size of the property.