As part of a European Directive, an Energy Performance Certificate (EPC) is mandatory if you intend to sell or rent your property.

EPCs will provide information on a building's energy efficiency using a sliding scale - 'A' being the most efficient, to 'G' the least efficient (see example graph). In addition to the Energy Efficiency Rating (relating to running costs), the EPC will also show the Environment Impact Rating (relating to the carbon dioxide emissions). An EPC report will make recommendations of how you can improve the rating of your property however; there are no statutory requirements to carry out any of the recommended energy efficiency measures.

Only qualified, accredited domestic energy assessors and qualified, certified home inspectors can produce EPCs for domestic properties. They analyse how homes are constructed, insulated, heated and ventilated, and the type of fuel being used.

Once your property has been given an EPC, it gets a unique number and is registered on a national database by the assessor. You can download extra copies by using the report reference number on the top right-hand side of the certificate.

Sellers are required to commission, but won't need to have received an EPC before marketing their property.