Energy Performance Certificates (EPCs) are an essential tool to evaluate the energy efficiency of properties. Represented by a scale of letters (A to G) and numbers (1-100), an EPC certificate provides insights into a building’s energy usage and environmental impact. For property owners, tenants and potential buyers, understanding these ratings is key to making informed decisions.

Improving energy efficiency not only saves money on energy bills but also reduces energy waste, powering a more sustainable future. This article takes a deeper dive into EPC ratings and explores their implications.

Understanding EPC ratings: Domestic Properties

The letter scale (A-G)

• A (92-100): Outstanding energy efficiency, requiring minimal energy to heat and power the property.
• B (81-91): Very efficient; minor upgrades could push it to an A.
• C (69-80): Above average; common for newer homes.
• D (55-68): Average efficiency, often found in older but well-maintained properties.
• E (39-54): Below average; improvements are likely needed to lower energy bills.
• F (21-38): Poor efficiency, indicating high energy use and costs.
• G (1-20): Very inefficient; urgent upgrades are typically necessary.

The numbers

The numeric score refines the letter banding further. For example, a score of 79 (C) is much closer to a “B” than a 69 (C). This granular view helps property owners see their progress as they implement efficiency upgrades.

Understanding EPC ratings: Commercial properties

The letter scale (A-G)

• A (0-25): Outstanding energy efficiency, requiring minimal energy to operate.
• B (26-50): Very efficient; minor upgrades could push it to an A.
• C (51-75): Above average; often seen in modern, well-designed buildings.
• D (76-100): Average efficiency; improvements may be necessary to enhance performance.
• E (101-125): Below average; upgrades will likely be needed to reduce operating costs.
• F (126-150): Poor efficiency, indicating high energy consumption and expenses.
• G (151+): Very inefficient; urgent improvements are required to comply with regulations and reduce

The numbers

Commercial EPCs emphasise operational energy consumption, with numeric scores helping businesses identify how their property ranks within its respective letter grade.

Why is your EPC rating important?

For domestic properties:

• Financial savings: Properties with ratings of C or better are more energy-efficient, lowering energy bills.
• Market appeal: Homes with A or B ratings are attractive to buyers and renters.
• Sustainability: Properties with good EPC ratings will also have reduced carbon emissions, supporting environmental goals.

For commercial properties:

• Regulatory compliance: Meeting Minimum Energy Efficiency Standards (MEES) is crucial to avoid penalties.
• Cost savings: Energy-efficient commercial properties lower operating costs.
• Business reputation: A strong EPC rating enhances corporate sustainability initiatives and marketability.

Factors affecting your EPC rating

Heat loss and insulation
Efficient insulation, including cavity wall insulation, double glazing, loft insulation and draught proofing, prevents heat loss, improving both numeric scores and letter grades.

Heating systems and energy sources
Modern heating systems, like heat pumps, score higher on EPC assessments due to their efficiency and sustainability.

Lighting and appliances
Using LED light bulbs and energy-efficient appliances can bump up your EPC rating by reducing overall energy consumption.

Unique cases: listed buildings
While harder to upgrade, listed buildings can achieve modest improvements in their EPC rating with sensitive changes, such as secondary glazing.

How to improve your EPC rating

1. EPC rating check

Review your EPC certificate to locate areas where your property scores poorly.

2. Simple improvements to boost numbers

• Replace traditional light bulbs with LEDs.
• Upgrade to modern, energy-efficient appliances.
• Improve insulation, such as loft and cavity wall insulation.

3.Major improvements for letter grade jumps

• Install a heat pump or upgrade your boiler.
• Switch to renewable energy sources like solar panels.
• Replace single-glazed windows with double or triple glazing.

4.Tailored improvements for commercial properties:

• Conduct an energy audit to identify inefficiencies.
• Upgrade HVAC systems to more energy-efficient models.
• Invest in renewable energy systems to reduce carbon footprint and operating costs.
• For more accurate and detailed energy performance assessments, Dynamic Simulation Modelling (DSM) can be used when producing EPCs. DSM considers factors such as hourly weather patterns, building orientation, and complex geometry, providing a deeper understanding of energy efficiency opportunities.

5. Get support
An energy assessor can recommend tailored solutions to improve your EPC score. In addition, an energy audit can identify further improvements. It will provide a comprehensive deep dive and review into all energy end users, identifying how and when energy is currently used across your sites.

The outcome is a comprehensive project register of energy saving measures, detailing quantified costs, savings and an estimated return on investment of each opportunity. This approach can help to identify quick wins for immediate cost savings that can be reinvested into energy efficiency projects.

Legal implications: Minimum Energy Efficiency Standards (MEES)

Domestic Properties

Introduced by the UK government, MEES regulations require rented properties in the private sector to meet a minimum EPC rating of E.

Commercial Properties

Since April 2018, it has been unlawful to grant new leases for non-domestic properties in England and Wales that do not meet the standard. These regulations extended to all privately rented commercial properties from April 2023.

• Current standard: EPC rating of E.
• Future standards: Moving to a C rating by 2027 and a B rating by 2030.
• Failure to meet MEES standards can result in significant penalties, including fines and restrictions on letting or selling properties. By proactively improving your EPC rating, you ensure compliance, reduce the risk of fines, and increase the value and marketability of your property portfolio.