What is an Energy Performance Certificate (EPC)

EPC rating

When you want to sell your house or if you’re a landlord who wants to rent out a property you’re told that you need an EPC.  Sometimes you might be asked for your property’s EPC rating.

But what is an EPC?  How is it calculated?  What does it tell you?  What is an EPC rating?

What is an EPC?

Quite simply, an Energy Performance Certificate shows how energy efficient a building is, how efficient it could be and how to get from one to the other.

How is an EPC calculated?

A domestic energy assessor, the person qualified to produce an EPC for your property, is taking into account three main things:

  • The size of your property.  The first thing an assessor will do is to measure the volume of your property.  This shows them the exact amount of space that needs to be heated.
  • How you heat your property.  Do you have a gas boiler?  If so, how efficient is it?  If not, what energy source do you use to heat your home?  What emits the heat? (underfloor, radiators) How do you control that heat? (timer, TRVs, room thermostat)
  • How do you keep that heat and energy  inside your property?  In other words, once you heat up your property, how easy is it for the heat to escape?  Do you have decent loft, wall insulation?  Double glazing?  Draught proofing?

What does it tell you?

Your EPC will tell you how efficient your property is and how efficient it could be.  It will also have a list of measures which would improve the property’s energy efficiency.

For example, if the property has cavity walls which have not been insulated, it will show how much more efficient the installation of the insulation would make it.

What is an EPC Rating?

The EPC will give you two scores out of 100 for your property.  These scores correspond to a letter rating system from A-G (with A being the most energy efficient.)

The first score shows you the current EPC rating of the house, the second score shows the EPC rating should all of the energy efficiency measures be installed.