All terms
legal
EPC (Energy Performance Certificate)
A government-issued certificate showing a property's energy efficiency on an A–G scale. Required for any sale or letting; valid for 10 years.
In simple terms
An energy rating like you see on a fridge, but for a house.
Example
A 1960s terrace might rate D (55–68 score). Upgrading insulation and windows could push it to a C — improving resale and rent prospects.
If you're buying
Sub-C ratings affect mortgages, insurance and future rental yields under MEES.
If you're selling
An EPC is legally required to list a property. A registered domestic assessor can arrange one for around £60–120 if missing.