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Out of all the services we offer, the Energy Performance Certificate is the one most widely recognised by the public. 

EPC ratings are plastered all over estate agent windows, homebuyers need them to complete contracts, and tenants use poor-performing certificates to challenge their landlords. 

The message EPCs deliver is instantly recognisable: a rainbow chart ranging from A-G, where green (A) is best, and red (G) is worst. Logic tells you the buildings in the green have the best energy efficiency. 

But do they? Public perception is slightly skewed from what the EPCs actually tell us. 

The Truth Behind EPC Graphics 

EPC ratings are based on running costs, not energy performance. An A rated house has the cheapest estimated bills, not necessarily the lowest energy consumption. 

The rating is based on the national average cost of fuel (whether that be electricity, gas or oil), and only considers the energy required for heating, hot water, ventilation and lighting. 

This causes confusion with the public, as the monetary value quoted on the report doesn’t correlate with the money they’re paying to their energy suppliers.  

When EPCs were launched in 2008, this was the first time the performance of all dwellings was compared using the same, standardised approach. But we’re now using EPCs to target building regulations (in Wales), and to set minimum standards for green mortgages – it was never designed for carrying this level of responsibility. 

And with the level of interest in EPC ratings set to continue, work is now underway to change how results are presented, bringing the biggest change in EPC history. 

What Will the New EPC Look Like? 

At this stage, the Government hasn’t committed to specific changes or implementation dates, so keep an eye out for news in the coming months. 

We are expecting the single A-G rating to be replaced with a dashboard of information. 

The new EPC will include several results for every dwelling, so the reader can focus on the section that interests them. There are six results being considered, but it’s unlikely all six will make it onto the final dashboard. 

• Fabric performance is likely to take a leading role. The familiar green to red graphic is expected, but the rating will be based on insulation quality and air permeability. 

• Fuel costs are still likely to feature in the new EPC, but it’s hoped a new calculation can be used to improve accuracy against people’s real fuel bills. 

• An energy use metric could consider how much fuel is required over the course of the year, minus any power the house generates itself through solar panels. 

• A carbon emissions rating would be useful on older homes but will have less importance on new-builds where all-electric heating will automatically mean a very low carbon footprint. 

• Heating system efficiency checks would encourage homebuyers towards heat pumps. Fossil fuel heating systems, such as gas and oil boilers, would score poorly in this section. 

• And the final potential metric is called ‘Smart Readiness’. This will consider the building’s ability to adapt to a Smarter energy grid. Load-shifting appliances, batteries, and intelligent thermostats can use electricity when the UK energy mix is greener. 

Scotland is expected to launch the new-look EPC in 2026. England and Wales are likely to adopt it as part of the Approved Document Part L changes, which will also introduce the replacement of SAP assessments with the Home Energy Model. 

There will then be a transitional window, where both old and new EPCs are in circulation. This could be as long as 10 years, as that’s the current validity period for certificates. 

We’ll publish further articles on this story when we receive certainty on the new EPC format, and when the changeover is due to happen.