Why Did my EPC Assessor Get my EPC Wrong?

As a property owner, you may have recently received your Energy Performance Certificate (EPC) and found that it does not accurately reflect the energy efficiency of your property.

Here are some potential reasons why your EPC assessor may have got your EPC wrong.

Inaccurate Data Collection

One possible reason why your EPC assessor may have got your EPC wrong is inaccurate data collection. EPC assessors need to collect a wide range of information about your property, such as the age and construction type of the property, its insulation, heating system, and lighting. Failure to collect accurate and reliable data can result in an incorrect EPC rating.

Examples of inaccurate data collection may include:

- Inaccurate or incomplete property plans or drawings

- Failure to accurately record insulation types and thicknesses

- Failure to measure the exact size of rooms and their volume

- Lack of knowledge of the variations in heating systems across different property types

Technical Issues with the EPC Software

The EPC software used to generate EPC reports is complex, and technical issues can sometimes cause the software to produce an incorrect rating. For example, technical glitches in the system can result in incorrect values being entered automatically, leading to an error in the final report. 

Examples of technical issues may include:

- Software bugs that have not been detected or resolved

- Inability to add the correct building elements to create a comprehensive report

- Incorrect calculations due to software glitches

Changes to the EPC Methodology

Since its introduction in 2007, the EPC methodology has undergone several updates to reflect changes in technology, construction methods, and government policies. Some of these changes may not have been known to your EPC assessor or could have been implemented after your EPC assessment. This means that your EPC rating may not accurately reflect the current energy efficiency of your property.

Examples of changes to the EPC methodology may include:

- Changes in building regulations

- Updates to energy efficiency standards

- Introduction of new renewable energy technologies that were not available at the time of your assessment

EPC Assessor Bias

Although very rare, there are cases where EPC assessors may provide inaccurate ratings due to bias. This could be due to the assessor's lack of knowledge of certain aspects of the property, their operating outside established guidelines, or a conflict of interest. If you feel that your EPC assessor may have made an error due to bias, you should discuss the issue directly with your assessor or contact the accreditation body. 

Examples of EPC assessor bias may include:

- Assessor favoritism or discrimination towards certain types of property/client

- Ignorance or lack of knowledge of energy efficiency concepts

- Assessor operating outside the established guidelines to complete the report

- Conflict of interest due to external factors such as financial gain or personal relationships

In conclusion, several factors can contribute to your EPC assessor getting your EPC wrong. Understanding these factors can help you to identify and address potential issues with your EPC rating. You may want to speak to an energy efficiency expert who can advise you on the best steps to take.