Energy Performance Certificates have been introduced to monitor energy efficiency in buildings and the legislation also makes it a legal requirement that certain public buildings (buildings with a total useful floor area over 1,000m 2 that are occupied by a public authority or an institution providing a public service - further defined as 'one providing a service traditionally associated with local or national Government' - to a large number of persons and therefore visited by those persons) have to display a different type of energy efficiency certificates, a DEC, and, if sold or rented, Energy Performance Certificates too.

The Energy Performance Certificate is a key method the government are using to try and deal with climate change and our carbon footprints. The Energy Performance Certificates are useful in that it monitors the quality of the UK building stock when it comes to carbon emissions and is based on the type of building, heating and lighting, whilst Display Energy Certificates differ in that they are based on actual fuel consumption and therefore monitor the way the building is used. Both are very useful in showing the energy efficiency of the building, though DECs, which are annually renewed, are better at encouraging occupiers to reduce emissions

If you are selling or renting a commercial property you do not need to collate energy consumption data in an energy survey in order to obtain the relevant type of energy efficiency certificates (which are commonly called Energy Performance Certificates). However, actual meter readings and details of any other fuel consumption data must be collected for a whole year for the accurate production of Display Energy Certificates.