An Energy Performance Certificate (EPC) rates a property's energy efficiency from A (most efficient) to G (least efficient). It's a legal requirement when a home or commercial unit is built, sold, or let in England and Wales.

What the rating actually measures

An assessor looks at insulation, heating systems, windows, lighting and construction to estimate running costs and carbon emissions, then produces a certificate valid for ten years.

Worth checking early: a property's current EPC rating and its recommendations report, since both are usually available on the government's EPC register before you view.

Why the rating matters

  • Running costs — a lower-rated property is likely to cost more to heat and power
  • Mortgage and letting rules — certain lenders and, for rental property, legal minimum standards can depend on the rating
  • Improvement potential — the certificate lists specific recommended upgrades and their approximate cost and saving

Do I need a new EPC if I'm buying a resale property?

Not necessarily — an existing valid EPC (less than ten years old) can usually be used, and the seller or agent should provide it as part of the sale.

Can I improve my rating cheaply?

Simple measures such as loft insulation, draught-proofing and LED lighting are often the lowest-cost ways to move up a band, though the certificate itself will list options specific to your property.

This guide is for general information only. Always check the current, valid EPC for the specific property you're considering.