A Display Energy Certificate (DEC) shows the actual energy performance of a public building. It uses the building’s metered energy consumption rather than relying solely on it’s physical characteristics. The DEC then provides an operational energy rating from A (most efficient) to G (least efficient).

In England and Wales, certain public buildings with a total useful floor area of more than 250m² require a DEC. This applies where a public authority occupies all or part of the building and members of the public frequently visit. Examples include schools, colleges, council offices, healthcare facilities, leisure centres and other qualifying public buildings.

The certificate must be displayed in a prominent position where the public can clearly see it. An Advisory Report, also accompanies the certificate. This report recommends ways to improve the building’s energy performance.

Each certificate provides;

*An operational energy rating from A (most efficient) to G (least effeicient)

*A comparison against similar building types

*Historical operational ratings (where applicable)

Certain public buildings in England and Wales require a Display Energy Certificate (DEC). A building must have a DEC where all three of the following apply:

• A public authority occupies all or part of the building.
• It has a total useful floor area of more than 250m²
• The building must be open to the public and be visited regulary.

As a result, many public-sector buildings require Display Energy Certificates. These include council offices, schools, colleges, universities, NHS buildings, healthcare facilities, public leisure centres, libraries and other qualifying public-sector buildings.

Where a DEC is required, the occupier must display in a prominent position where the public can clearly see it. The occupier must also have a valid Advisory Report containing recommendations for improving the building’s energy performance.

Private businesses and organisations do not normally need a DEC, even if they occupy a large building. Nevertheless, private organisations can choose to obtain a DEC voluntarily. They may instead require a Commercial EPC, depending on the circumstances.

At ECC, we can help determine whether your building requires a Display Energy Certificate. We can arrange the appropriate DEC assessment and Advisory Report to help keep your organisation compliant.

For buildings over 1,000m², the occupier must renew the DEC every 12 months. The accompanying Advisory Report is valid for 7 years.

For buildings between 250m² and 1,000m², both the DEC and Advisory Report are valid for 10 years.

A DEC reflects the building’s actual operational energy performance, using metered energy consumption. For larger public buildings, annual renewal therefore provides an ongoing picture of energy performance. It also allows organisations to compare energy performance from year to year.

The Advisory Report complements the DEC by identifying ways to improve energy efficiency. Recommendations may include improvements to the building fabric, heating, ventilation, and lighting.

A DEC provides valuable insight into how efficiently an organisation manages a building during day-to-day operation.

Benefits include:

• Demonstrating legal compliance
• Meeting public sector sustainability objectives
• Identifying opportunities to reduce energy consumption
• Lowering utility costs
• Supporting Net Zero and carbon reduction strategies
• Increasing awareness of building energy performance
• Encouraging continual improvement through annual monitoring

Importantly, DECs use actual energy consumption rather than predicted performance. This provides a realistic picture of how efficiently a building is operating.

Although a Display Energy Certificate and an Energy Performance Certificate both assess building energy performance, they serve different purposes. In particular, they measure energy performance in different ways.

A DEC measures how a building is actually performing in use. It uses metered energy consumption, such as electricity and gas usage, to calculate an Operational Rating. The rating runs from A (most efficient) to G (least efficient). DECs mainly apply to qualifying public buildings that are frequently visited by the public.

A Commercial EPC, on the other hand, assesses the calculated energy performance of a non-domestic building. It considers factors such as its construction, insulation, heating, cooling, ventilation and lighting systems. Commercial property owners commonly need an EPC when they construct, sell or let a property.

Put simply:

EPC = the building’s calculated energy efficiency based on it’s design, fabric and services.
DEC = the building’s actual energy performance based on how much energy it uses.

As a result, the same building can have both an EPC and a DEC, and the ratings may be different. For example, a building may have an efficient design and modern building services, resulting in a good EPC rating. However, high energy use, through long operating hours or inefficient day-to-day management could result in a poorer DEC rating.

For organisations managing public buildings or larger property estates, both ratings can provide valuable information. The EPC identifies the building’s calculated energy efficiency, while the DEC shows its real-world operational energy performance.

If your building is legally required to have a Display Energy Certificate (DEC), failing to comply can result in financial penalties and enforcement action.

For qualifying public buildings in England and Wales, the occupier must display a valid DEC prominently where members of the public can clearly see it. The occupier must also hold a valid Advisory Report.

Failure to comply can result in:

• A £500 penalty for failing to display a valid DEC in a prominent place.
• A £1,000 penalty for failing to have a valid Advisory Report in your possession or control.

Paying a penalty does not remove the requirement to comply. You will still need to commission the appropriate DEC or Advisory Report, and continued non-compliance can result in further offences.

Compliance is therefore particularly important for schools, colleges, NHS buildings, council offices, leisure centres and other qualifying public buildings, especially where annual DEC renewals are required.

First thing we would advise is to check the official government register to check if you have a valid DEC certificate and Advisory Report in place. We are happy to check this on your behalf, before providing a quotation. Once this has been ascertained, and a quotation has been accepted we can then proceed to the next stage.

For a first DEC, the assessor will need to carry out a site visit and gather information about the building, including its floor area, occupancy and energy-related building services. You’ll also need to provide energy consumption data, ideally covering the previous 12 months, such as electricity, gas or other fuel meter readings and bills.

The process typically involves:

1. Gathering building information – including floor areas, building use, occupancy and relevant energy services.
2. Reviewing energy consumption – the assessor will collect and review 12 months energy consumption data.
3. Calculating the Operational Rating – the assessor uses Government-approved methodology and software to compare the building’s actual energy performance against an appropriate benchmark.
4. Preparing the Advisory Report – alongside the DEC, the assessor identifies recommendations that could improve energy performance, from low-cost operational measures through to potential improvements to building services and fabric.
5. Lodging the DEC and Advisory Report – the assessor lodges both documents on the national Energy Performance of Buildings Register and provides the DEC for you to display.

For subsequent DEC renewals, another full site survey may not always be necessary. Where the same assessor already knows the building and the occupier confirms confirms that nothing relevant has changed, the assessor may use updated energy consumption information alongside the existing building data.

At EnergyCore Compliance Ltd , we aim to make the DEC process as straightforward as possible. We’ll explain what information we need, review your available energy data and manage the assessment, certification and lodgement process through to completion.

The result is a compliant Display Energy Certificate and Advisory Report, together with a useful picture of how the building is actually performing and where opportunities may exist to improve energy efficiency.

Yes. At EnergyCore Compliance, we can coordinate Display Energy Certificates (DECs) and Advisory Reports across multiple buildings, providing a streamlined service for organisations responsible for larger property portfolios and public-sector estates.

Managing DEC compliance across numerous sites can involve significant administration, particularly where buildings have different renewal dates and energy consumption data needs to be collected from multiple locations. Our portfolio service is designed to reduce that administrative burden and provide one point of contact for your DEC requirements.

We can help coordinate site surveys, energy data collection, DEC assessments and Advisory Reports, while keeping track of certification and renewal requirements across your portfolio.

This service is particularly suited to local authorities, schools and academy trusts, colleges, healthcare organisations, housing associations and other public-sector bodies responsible for multiple qualifying buildings.

Whether you require DECs for a handful of properties or a large multi-site estate, our aim is to make ongoing Display Energy Certificate compliance easier to manage, giving your team greater visibility across the portfolio while reducing the time spent coordinating individual assessments and renewals.

No. Unlike Commercial EPCs, there is currently no minimum energy rating that a Display Energy Certificate (DEC) must achieve.

A DEC gives a public building an Operational Rating from A to G, based on its actual energy consumption. An A rating represents very efficient energy performance, while a G rating indicates high energy consumption compared with the relevant benchmark.

This is different from Commercial EPCs, where qualifying privately rented properties may need to meet a minimum EPC rating under the Minimum Energy Efficiency Standards (MEES). There is no equivalent MEES minimum rating for a DEC, so receiving a D, E, F or G DEC rating does not in itself make the building non-compliant.

The legal requirement is to obtain and display a valid DEC where one is required and to hold a valid Advisory Report. However, a poor DEC rating can highlight opportunities to improve the way the building uses energy and reduce operating costs.

The accompanying Advisory Report provides recommendations for improving energy performance, helping building managers understand where changes to building services, controls, energy management or the building itself could potentially reduce consumption.

For organisations managing multiple public buildings, DEC ratings can also be useful for comparing operational energy performance across an estate and identifying buildings that may benefit from further investigation or energy-efficiency improvements.

No. Although a Display Energy Certificate (DEC) is accompanied by an Advisory Report, there is currently no legal requirement to carry out the energy efficiency improvements recommended within the report.

The Advisory Report is designed to help building owners and occupiers understand where opportunities may exist to reduce energy consumption, improve operational energy performance and potentially lower running costs. Recommendations may relate to areas such as heating, cooling, ventilation, lighting, building controls, energy management or the building fabric.

The recommendations are advisory rather than mandatory, so they do not all need to be implemented for the building to remain compliant with DEC requirements.

However, the report can be a useful tool for energy and facilities management, particularly where a building has a poor DEC rating or an organisation is looking to reduce energy use and carbon emissions. It can also help organisations responsible for multiple public buildings identify and prioritise potential improvements across their estate.

The UK Government continues to review and modernise building energy assessment frameworks as part of its wider Net Zero strategy. While current DEC requirements remain in place, public sector organisations are under increasing pressure to improve operational energy performance, reduce carbon emissions and demonstrate greater environmental responsibility.

Maintaining accurate and up-to-date DECs, together with implementing the recommendations within Advisory Reports, helps organisations prepare for future regulatory changes while delivering measurable energy savings.