What is an Energy Performance Certificate (EPC)
The Energy Performance Certificate is a legal requirement for all house sales.It also acts as a stand alone report for a property letting.
An EPC provides details of a property's CO2 emissions and approximate annual heating costs. The report will offer advice for improving the energy efficiency of the property together with an indication of associated running cost savings.
EPC's have two ratings:  
Home Energy Efficiency
this provides you with an overall calculation
on the efficiency of your home
Grades are given on a scale of A - G
A = very efficient and low environmental impact
G = very inefficient and high environmental impact
Most new properties are Grade B/C
Grade D/E is the UK average
Environmental Impact Rating
This is a measure of a homes
 impact on the environment.
(it's Carbon Emission level) 
The higher the rating (A),the
 less impact it has.
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