(DEC) Display Energy Certificates

Professional DEC Assessments 

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O.M Energy Assessments provides accredited Display Energy Certificate (DEC) assessments for public and commercial buildings across the UK. We support building owners, facilities managers, local authorities, and NHS estates in meeting statutory energy performance and compliance requirements.

Our DEC services are delivered by fully qualified and insured energy assessors, ensuring accurate, reliable, and compliant certification every time.

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What Is a Display Energy Certificate (DEC)?

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A Display Energy Certificate (DEC) shows how energy-efficient a building is based on actual energy consumption, rather than design assumptions. The rating runs from A (most efficient) to G (least efficient) and must be clearly displayed in qualifying buildings.

DECs help organisations:

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• Demonstrate energy performance transparently

• Identify opportunities to reduce energy use and costs

• Meet legal obligations under UK energy regulations

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Who Needs a DEC?

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A DEC is legally required for buildings that:

• Are occupied by a public authority

• Are frequently visited by the public

• Have a total useful floor area over 250 m²

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Renewal requirements:

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• 250 m² – 999 m²: DEC valid for 10 years

• 1,000 m² and above: DEC must be renewed annually

An Advisory Report is also required:

• Every 7 years (or when a new assessor is appointed)

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Our DEC Assessment Service

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At O.M Energy Assessments, we provide a complete DEC service, including:

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✔ Review and validation of energy consumption data
✔ On-site building inspection
✔ Accurate DEC calculation and registration
✔ Advisory Report with practical energy-saving recommendations
✔ Guidance on compliance, display requirements, and renewals

 

We handle the process efficiently to minimise disruption to building occupants.

 

Buildings We Assess

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We regularly carry out DEC assessments for:

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• Schools, colleges, and universities

• NHS buildings and medical centres

• Council buildings and civic centres

• Leisure centres and libraries

• Courts, police stations, and fire stations

• Other public-sector and publicly accessible buildings

 

Why choose O.M Energy Assessments?

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• Accredited & experienced DEC assessors

• Clear, fixed pricing – no hidden fees

• Fast turnaround times

• Practical advice to improve energy performance

• Nationwide coverage

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We understand the pressures on public-sector estates and deliver a professional, compliant service you can rely on.

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Improve Your Energy Performance

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Your DEC is more than a legal requirement — it’s a powerful tool to:

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• Reduce operational energy costs

• Improve sustainability credentials

• Support carbon reduction strategies

• Demonstrate environmental leadership

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Our Advisory Reports provide clear, achievable recommendations tailored to your building.