Display Energy Certificates (DECs)
Operational Rating DECs for public buildings and Section 63 deferral in Scotland.
What it is
A DEC displays the actual metered energy performance of a building based on 12 months of consumption data, published on a public certificate. DECs are also used as a Section 63 deferral route in Scotland.
Who needs it
Public authorities occupying buildings over 250m² visited by the public, and Scottish commercial building owners using the DEC deferral route under Section 63.
When it's required
Annually for public buildings over 1,000m²; every 10 years for public buildings 250–1,000m². At Section 63 trigger points in Scotland where deferral is elected.
What we provide
- [01]Operational Rating assessment and DEC production
- [02]Advisory Report with recommended measures
- [03]Portfolio DEC programmes for public sector estates
- [04]Section 63 deferral DECs in Scotland
Related services
Section 63
Approved Section 63 Advisor services for non-domestic buildings in Scotland at sale or new lease.
02Commercial EPCs
Level 3, 4 and 5 non-domestic Energy Performance Certificates, with an enhanced EPC+ option for portfolio strategy.
03E&S Statements
Planning-ready energy and sustainability statements for major developments.
How this compares
Side-by-side breakdowns of the standards and routes most often confused with this service.
EPC vs DEC
An EPC rates how a building was designed and built; a DEC rates how much energy it actually consumed over the last 12 months.
Asset rating vs Operational rating
An asset rating scores the building as designed under standard conditions; an operational rating scores what the building actually consumed in use.
Common questions
[01]Who needs a Display Energy Certificate?+
Public authorities occupying buildings over 250m² frequently visited by the public need a DEC. In Scotland, DECs can also be used as a Section 63 deferral route.
[02]What is a Display Energy Certificate (DEC)?+
A Display Energy Certificate shows the actual measured energy use of a public building over the previous 12 months, rated A to G, and must be displayed where visitors can see it. Unlike an EPC, which rates the building's design, a DEC rates how the building is really being operated.
[03]Which buildings need a Display Energy Certificate?+
Public authority buildings frequently visited by the public and over 250m² of useful floor area require a DEC. Buildings over 1,000m² need a DEC renewed annually with a 7-year advisory report, while those between 250m² and 1,000m² need a DEC every 10 years.
[04]Why does my building's EPC rating not match its energy bills?+
An EPC is an asset rating that models a standardised pattern of use, while your bills reflect real occupancy, hours, equipment and behaviour. A building can hold a good EPC and still perform badly in use, which is exactly the gap a DEC or a TM54 operational energy assessment is designed to expose.
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