Energy Performance Certificates: guide

Guidance on the use of Energy Performance Certificates (EPCs) which provide information about how energy efficient a building is, and how the efficiency could be improved.

Assessment process

Survey visits

Each dwelling for which an EPC is produced must be visited as part of the assessment. The visit should ensure that the data collected is verified as accurate for that property.

An assessor may not always need to revisit a property if they have recently collected evidence from that property. The assessor should record and justify their approach to using an earlier visit. They should note and address the risk of changes depending on the time between visits.

Information collected

The EPC assessment records specific information about a building.

This includes:

  • the size and layout
  • how it has been constructed
  • the way it is insulated, heated, ventilated, and lighted

People use buildings in different ways so the calculation is based on standard assumptions about the number of occupants and the way they use the building. The property must be visited to ensure the information entered is accurate.


The EPC is produced using a calculation methodology that is owned by UK Government, and approved for use in Scotland by Scottish Ministers. Further technical information about the calculation methodologies can be found on the Building Research Establishment website:

Energy efficiency recommendations

The EPC also includes recommendations to improve the efficiency of the building. Potential improvements are assigned on the EPC where they are relevant to the building, but this assessment is not a substitute for bespoke retrofit advice.

There is no requirement to carry out these recommendations. However by seeking further advice and implementing measures you could improve the energy efficiency of your building and reduce your energy bills over time.

For advice and information about making your home more energy efficient, contact Home Energy Scotland.

EPC energy costs and actual bills

The purpose of the EPC is to allow the efficiency of buildings to be compared on a like for like basis. As such, the costs shown on an EPC are not intended to accurately represent an individual’s energy use.

The energy costs shown on an EPC are calculated using frequently updated cost files and standard assumptions. This includes assumptions about the way the property is occupied and used. Additionally, the EPC does not assess the energy used for cooking or appliances.

Record keeping

An assessor must retain the data used for EPC calculation and evidence that the data relates to the assessed property. This information may be required if the EPC is audited.

EPC data

We publish EPC data on We publish this to help promote energy efficiency and for research purposes. This data does not contain personal information.



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