An Energy Performance Certificate shows the official energy efficiency rating of a property. As a homeowner, you'll only need one when you sell your home. From 1 August 2007, in order to sell your home you'll need an Energy Performance Certificate apart of your Home Information Pack. If you're not planning to sell your home, you don't need to do anything.

The certificate provides you with a rating for the building, showing its energy efficiency and its environmental impact on a scale from A-G (where A is the most efficient and G the least efficient), in graphical format. It also contains recommended ways to improve the building's energy performance.

By 2009, all buildings in the UK that are constructed, sold or rented out will have to have an Energy Performance Certificate, in accordance with the European Energy Performance of Buildings Directive.

Predicted and interim energy assessments
Predicted energy assessments are for homes that are not yet built. When a home is designed, a predicted energy rating based on the design is produced. This must achieve, as a minimum, the target energy rating laid down for the home as specified by the energy efficiency requirements of building regulations.

Interim energy assessments are for new homes built in accordance with the energy efficiency requirements of the building regulations that came into force in April 2006. For these homes, until 1 October 2007, only the energy-efficiency and environmental-impact graphs will be required, and not the full Energy Performance Certificate.