Compliance Comparison: DECs and EPCs

Lately, we’ve been answering lots of enquiries about Display Energy Certificates (DECs) and Energy Performance Certificates (EPCs) so we have decided to put them head to head to help you determine when you might need one and not the other.

Both DECs and EPCs were introduced in 2008. These certificates rate the energy performance of buildings but are required in different circumstances:

  • DECs for public buildings with funding from the public sector and a floor area of over 250m2, which need to be displayed at all times
  • EPCs for all buildings when they are constructed, sold or rented out.

So, how else do they compare?




A DEC measures the actual energy usage of a building (Operational Rating) based on annual consumption.

Measures the energy efficiency of the building based on the type and level of insulation in walls and roofs, and the efficiency and type of services such as lighting, heating or mechanical ventilation.

Who are the applicable to?

Legally required for all buildings which are accessed by members of the public. 

Legislation applies to properties with a floor area of 250m2 or more, that receive public sector funding and are accessed by the public.

All buildings when constructed, rented or sold.

Legislation applies to all commercial and domestic properties.

What is their format?

Certificate that shows the Operational Rating grading from A (lowest energy consumption) to G (highest energy consumption). It also shows historical Operational Ratings. 

A DEC must be clearly displayed at all times in a prominent place and must be accompanied by a valid Recommendation Report; this contains energy saving tips that were identified as part of the site survey. 

Certificate that shows the energy efficiency and carbon emissions of a building using Asset Ratings grades from A (very efficient) to G (very inefficient).

A Recommendation Report accompanies an EPC and contains suggestions for ways to change the fabric or heating of the property that would improve the energy rating.

Who is responsible for them?

The public authority, relevant institution or building occupier is responsible for obtaining and displaying a DEC for each building affected by this legislation. 

Builders or persons responsible for the construction need to provide new owners with this certificate. Then it’s the building owner’s responsibility. 

When do you need one?

Buildings over 1,000m2 need to renew their DECs annually. DECs for smaller buildings, under 1,000m2, are valid for 10 years.  Accompanying Recommendation Reports are valid for seven years for larger building and ten years for smaller buildings. 

An EPC is valid for 10 years. If there have been major renovations to a property, a new EPC is required. A valid EPC is needed when the property is leased or sold. The accompanying Recommendation Report gets renewed along with the certificate.

Are there penalties?

To comply with the Energy Performance of Buildings Regulations, valid Display Energy Certificates must be displayed in a prominent location, and the Recommendation Report be available to review upon request. Organisations failing to adhere face a fine of £1,500.

The owner or landlord of a property for sale or let can be fined between £500 and £5,000 for failing to make an EPC available to any prospective buyer or tenant. 

For a full overview of our compliance service you can either visit our DEC service or our non-domestic EPC service page. If you would like more information, call us on 01908 690018, or contact us here.

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