Energy Performance Certificates (EPC) Explained
An Energy Performance Certificate (EPC) rates a building's energy efficiency and is required at key transaction points. This guide explains what an EPC is, when you need one, and what the rating means.
In short
An Energy Performance Certificate (EPC) rates a building's energy efficiency from A (most efficient) to G (least efficient). It is required when most buildings are built, sold, or let, is valid for ten years, and includes recommendations for improving efficiency.
When an EPC is required
An EPC is generally required whenever a building is constructed, sold, or let, with some exemptions (for example certain listed buildings and temporary structures). For commercial property, the EPC is produced by an accredited assessor and must be made available to prospective buyers or tenants. The certificate shows the asset rating on the A–G scale and lists recommended measures to improve performance.
MEES and minimum standards
EPC ratings have real commercial consequences through the Minimum Energy Efficiency Standards (MEES). For most commercial lettings in England and Wales, it is unlawful to let a property below a minimum EPC rating (currently E, with tighter standards proposed over time). This makes the EPC rating a factor in whether a building can be let at all, driving investment in efficiency improvements to maintain lettability — a key concern for landlords and asset managers.
Improving an EPC rating
The EPC's recommendation report identifies measures to improve the rating — better lighting and controls, heating and cooling upgrades, insulation, and improved metering and management. Realising these improvements depends on understanding the building's current systems and how they are operated and maintained. Accurate documentation of plant, controls, and energy data underpins both the assessment and the improvement works that follow, helping target the changes that will most improve the rating.
How this applies by sector
Sources
The regulatory positions on this page come from the following primary sources. Where guidance and legislation differ, the legislation governs — always confirm the requirements that apply to your own site and jurisdiction.
Frequently asked questions
How long is an EPC valid?
What is a good EPC rating?
What is MEES?
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