Staggeringly Inaccurate

This was the view of Martina Lees, writing in the Sunday Times recently when describing EPCs. In the article, she claims that taxpayers, homeowners and landlords face paying billions of pounds to upgrade their homes, but this investment will make little difference to the energy efficiency of their homes.

The legal standard

Tom Entwistle takes up the theme in his article on Landlord Zone where he references further research which claims that 2.5 million EPCs are inaccurate. He highlights the gravity of this situation given they are the legal standard for sales and lettings and increasing a gateway to a mortgage. 

What are the issues? 

One of the primary issues with EPCs is the inconsistency in the methods used by different assessors. The accuracy of the certificate is reliant on the expertise and thoroughness of the assessor, which can lead to varying results. In some cases, assessors may not have the necessary experience to correctly identify and evaluate the energy efficiency measures implemented in a building. This results in a misleading representation of the building's energy performance.

Lack of Real-World Data

EPCs are based on theoretical models and calculations, rather than real-world data. This means that they do not account for the actual energy consumption of a building and its occupants. Factors such as occupant behavior, appliances, and heating systems can significantly impact energy use, but these elements are not reflected in the EPC rating. 

Recent research in 17,000 properties has shown that actual energy usage was 91% lower than that calculated during the EPC assessment. 

None invasive assessment

Ratings are based on non-invasive visual inspections. This means that the data used is based on a visual inspection, which will necessarily require some assumptions to be made. Such assumptions reduce the accuracy of the process further.  

The result of this process is that many landlords undertake improvement work only to find that their overall score goes down. One of the key variables is the floor space and how accurately that is measured. It is often not measured correctly and this can cause major problems. 

What can be done?

The government already recognises the problems with the current system and has started a review. The objective is to produce accurate results and increase confidence in EPCs. 

This is going to be a vital part of the overall strategy if landlords are going to be compelled to invest in making improvements to reach EPC targets, there will need to be greater confidence in the results.