A DEC shows the energy performance of a building based on actual consumption as recorded annually. The DEC provides the Operational Rating (OR) of the building. The difference between an EPC and a DEC is that the EPC calculates a carbon emissions based index using information relating to building design, energy equipment and system specifications, whereas the DEC calculates the carbon emissions based index using information provided in utility bills as well as the type of building energy systems employed.
Since 1st October 2008 DECs have been required for a building meeting the following criteria below:
- Total useful floor area over 1000m2
- Owned, managed or operated by a public authority or organisation providing equivalent services to a public authority
- Frequently visited by a large number of members of the public
Additionally an advisory report accompanies a DEC and contains recommendations on how to improve the energy performance rating for the building. Current regulations state that the DEC has to be renewed each year, and the advisory report is valid for seven years providing no major changes have been made to the building. The DEC should be displayed at all times and clearly visible to the public.
Information relating to annual energy consumptions and other details relating to the use type and size of the building, as well as details of the energy supply systems employed will be input into the approved software. Appropriate options for improvements to the existing building and systems are included as the basis for the recommendations report.
We can provide the Display Energy Performance Certificate along with the advisory report. We can also carry out measured surveys on the property if required. All of our assessors are fully qualified to provide the DEC, and will be able to assist with any queries the client may have regarding the EPC, and the recommendations laid out in the advisory report.
Quotes for this work can normally be provided over the phone without a site visit, assuming that sufficient information is available which defines the size of the building, along with certain specific details of the building which will affect the OR and annual energy consumption figures.