Energy Performance Certificates (EPCs) are part of Home Information Packs, which have been in effect since 1 August 2007 in England and Wales for domestic properties with four or more bedrooms.

The scheme was extended to encompass three bedroom homes from 10 September 2007. Rental properties, which have a certificate valid for 10 years, required on a new tenancy commencing on or after 1 October 2008. They are a result of European Union Directive 2002/91/EC relating to the energy performance of buildings, as transposed into British law by the Housing Act 2004 and The Energy Performance of Buildings (Certificates and Inspections) (England and Wales) Regulations 2007.

The energy survey needed to produce an EPC is performed by an inspector who visits the property, examines key items such as loft insulation, domestic boiler, hot water tank, radiators, windows for double glazing, and so on.

He or she then inputs the observations into a software programme which actually performs the calculation of energy efficiency. The programme gives a single number for the rating of energy efficiency, and a recommended value of the potential for improvement. There are similar figures for environmental impact.

A table of estimated energy bills per annum (and the potential for improvement) is also presented, but without any reference to householder bills. The householder will have to pay for the survey, which costs around £60 for a four bedroom house.