Understanding the Difference Between EPC and EIR Ratings

3 Mins. Read


When assessing the energy efficiency of a domestic building, two key ratings will be published: the Energy Performance Certificate (EPC) rating and the Energy Impact Rating (EIR). These ratings provide valuable information about a building’s energy consumption, carbon emissions, and potential for improvement. In this article, we will delve into the details of each rating and explore the differences between them.

Energy Performance Certificate (EPC) Rating:

The Energy Performance Certificate (EPC) is a document that provides an assessment of a building’s energy efficiency. It is a legal requirement for domestic buildings in many countries, including the United Kingdom. The EPC rating is represented on a scale ranging from A (most efficient) to G (least efficient).

The EPC rating is based on various factors, including the insulation of the building envelope, heating systems, ventilation, and the use of renewable energy sources. A qualified energy assessor conducts an inspection and collects relevant data to calculate the EPC rating. The assessment takes into account factors such as the age of the building, construction materials, and the efficiency of appliances and lighting.

The EPC rating provides an overview of a building’s current energy performance and estimates its potential energy efficiency if recommended improvements are implemented. The certificate also offers recommendations for enhancing energy efficiency, reducing carbon emissions, and lowering energy costs. It serves as a valuable tool for homeowners, tenants, and prospective buyers or renters, enabling them to make informed decisions regarding energy usage and costs.

Energy Impact Rating (EIR):

The Energy Impact Rating (EIR) is a relatively newer concept and aims to complement the EPC rating by considering the broader environmental impact of a building’s energy usage. While the EPC rating focuses primarily on energy efficiency and cost, the EIR provides insights into a building’s carbon footprint and sustainability performance.

The EIR rating considers factors such as greenhouse gas emissions, the use of non-renewable energy sources, and the impact of the building’s energy consumption on climate change. It takes into account the energy consumed during the building’s operation and throughout its life cycle.

Similar to the EPC rating, the EIR rating is represented on a scale from A (low environmental impact) to G (high environmental impact). It provides a more holistic view of a building’s environmental performance and encourages the adoption of sustainable practices, such as the use of renewable energy sources, energy-efficient appliances, and responsible construction materials.

Differences Between EPC and EIR Ratings:

Focus: The EPC rating primarily assesses a building’s energy efficiency, while the EIR rating evaluates its broader environmental impact, including carbon emissions and sustainability considerations.

Factors Considered: The EPC rating focuses on factors such as insulation, heating systems, and renewable energy sources, while the EIR rating takes into account a building’s life cycle emissions, energy source sustainability, and other ecological factors.

Purpose: The EPC rating is mainly used to provide information to homeowners, tenants, and prospective buyers or renters regarding a building’s energy efficiency and potential for improvement. The EIR rating emphasises the environmental impact of a building’s energy consumption and encourages sustainable practices.

Complementing Each Other: While the EPC and EIR ratings have different scopes, they can be viewed as complementary tools. The EPC rating informs about energy efficiency and potential savings, while the EIR rating highlights the building’s ecological impact and guides towards sustainable choices.


Both the Energy Performance Certificate (EPC) rating and the Energy Impact Rating (EIR) play crucial roles in assessing a building’s energy efficiency. Interested in finding out your EPC and EIR rating? Click on this link and select Create My Plan and we will provide you with an instant result.

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