By Law all from the 1 October 2008, all properties need to have a valid Energy Performance Certificate (EPC)

What is an EPC?

The Energy Performance Certificate is broadly similar to the certificates found on many domestic appliances. A Certificate for a building gives the building an asset rating based on its energy efficiency, but doesn't take into account how the home is used by the occupiers. The certificate will give the building a rating from A to G. An A rating shows it's very efficient, meaning lower fuel bills, while G is inefficient, meaning higher fuel bills. The certificate will also show the building's environmental impact by indicating its carbon-dioxide emissions. 

Energy Impact Rating	Energy Efficiency Rating