Since January 2013, it has been stated as mandatory to display DECs for all public authority buildings and institutions which provide public services. These refer to buildings having a total floor area of over 500 m2. The buildings include libraries, public sport facilities, NHS trusts or education centres.
For buildings having a total floor area between 500 and 1000 m2 the DEC will be displayed for 10 years.
The aim of the display DEC is to show how energy efficient is the building which includes the assessment of the utilisation of the building. The DEC must not be mistaken with the EPC (Energy Performance Certificate) as the latter is showing how a building can perform and not how it is actually performing. Indeed, this is due to the fact that the assessment’s criteria are as follow:
– The type of building assessed
– The total floor area
– How the cooling and heating are used within the building
– The yearly energy bill.
The DEC also provides advice to how the energy can be improved by controlling the heating and cooling, the use of water, the type of lighting and the onsite energy generation (renewables, etc.).