Energy Efficiency and Environmental Impact
Energy Efficiency is self-explanatory, reflecting how effectively energy that is needed around the property is used. A higher rating means a more efficient use of energy. Environmental Impact is essentially a measure of how much carbon dioxide (CO2) is emitted from the property. The higher a rating on the Environmental Impact, the less CO2 is emitted.
EPCs show the current and potential energy usage of a property through the government’s approved Standard Assessment Procedure (SAP). The basic underpinning of the SAP rating is a points-based system ranging from 0 to 100. When a property has an EPC assessment it is given a SAP rating with a higher score denoting more efficiency.

EPC Bands
The SAP score has been divided into seven category bands that summarise a property’s energy efficiency and environmental impact:
The Department of Energy and Climate Change (DECC) has established that a property must have a minimum EPC rating of category D in order to receive the full Feed-in Tariff.

EPC Explained
Establishing a D rating
Properties will need at least 55 SAP points to be eligible to achieve a D rating. DECC have claimed that around 55% of UK domestic properties and approximately 65% of all commercial properties are already at this level.
EPC assessments can be arranged through any registered organisation and vary in cost. They are required before Feed-in Tariff applications can be submitted. 2020SolarPV are able to arrange this for you:
- An assessment for a home owner should take 2-3 hours.
- Commercial property owners should be aware that an EPC assessment will involve a more comprehensive and usually more expensive process.
There are quite a few ways you can improve energy efficiency to help achieving a D rating:
Validity
A domestic EPC remains valid for a period of 10 years, or until alterations affect the rating.
Exemptions
There are certain exemptions for the category D requirement for some properties:
- Places of worship (e.g. churches)
- Temporary buildings in use for less than 2 years (e.g. portable buildings, site buildings)
- Low energy demand buildings (e.g. farm outbuildings, barns)
- Stand-alone buildings less than 50 sq. m (e.g. sheds, summer houses)
- In general, commercial premises that are less than 50 sq. m Gross Internal Area