Frequently Asked Questions

• Some EPCs which appear to be inaccurate may boil down to common
misunderstandings about the EPC, and the energy assessment process.
• The assessment process is non-invasive, and the data collected is based on what an
assessor can see and the evidence available to them on the day of the assessment.
If, for example, they were unable to access a part of a property, then they may enter
‘no access’ in that part of the assessment form. In this case the methodology would
assume a default value when calculating the EPC.
• Moreover, EPCs for homes were first introduced in England and Wales in 2007 as a
cost metric, which means that the A to G rating simply indicates how cheap or
expensive a home would be to run. The EPC is also based on standard occupancy,
and does not take account of how the property is used and the condition it is
currently in.

• The EPC is based on a standard occupancy model. It makes assumptions based on
how this standard occupancy would use the heating, lighting and ventilation services
in a property. This approach is great for allowing you to compare similar homes across
the country, but it’s no good as a true estimate of your own household’s fuel bills. For
example, the EPC does not take account of energy use from domestic appliances
such as fridges, computers or TVs, and is based on fuel prices that may differ from the
tariffs the utility provider charges you.
• To get a true estimate of your personal energy usage in your specific property, you
need an occupancy assessment. This can be achieved for a domestic dwelling
(houses, flats etc.) by instructing a Retrofit Coordinator.

• This is to be expected. EPC calculation software automatically generates
recommendations using the rules specified in the national calculation methodology,
all of which are things that could improve the asset rating.
• It’s common for EPCs to recommend similar improvements, as these are proven
measures that will deliver the greatest EPC improvement and energy saving to a
property with standard occupancy. These include cavity and solid wall insulation, loft
insulation, floor insulation, smart controls, low carbon heating solutions such as heat
pumps, solar PV and solar thermal. It is also common to see other measures such as
LED light bulbs, hot water cylinder insulation and controls, and more.
• An EPC is working from a set of assumptions and a standardised occupancy model.
In its current format, it can’t take a household’s specific circumstances into account.
• Unfortunately, some potentially helpful recommendations cannot currently be shown
by the EPC. For example, it may make sense to recommend installing an air source
heat pump or other electric heating system instead of replacing a gas boiler,
because that will reduce carbon emissions. But because the EPC in its current format
just looks at energy cost, and because the cost of electricity is currently higher than
the cost of gas, the EPC will not typically display these as recommendations.

• Unfortunately not. The indicative costs are set by the national calculation
methodology, they are not made up or calculated by the assessor. We do agree that
sometimes these will appear to be too broad as a guide and obviously can’t reflect
exact prices from local installers.
• We would always recommend you use the recommendations to approach a range
of reputable installers for quotes for energy efficiency measures. Their quotes will take
into account the type of dwelling and specific situation.

The national calculation models can use make and models of heat pumps, when
they are identified and they exist in the products database. But some other, newer
technologies, such as infrared heating etc, are not within the current calculation
methodologies
• Currently, the Appendix Q database has a list of approved technologies, such as low
carbon heating solutions, that can be entered into the SAP calculation methodology.
Appendix Q and the process for including new technologies are currently being
consulted on by DESNZ as part of its plans for a new methodology, called the Home
Energy Model (HEM). Elmhurst supports this improved process to include new low
carbon technologies in a speedier, more pragmatic and agile way.

The Energy Performance of Buildings (Certificates and Inspections) (England and
Wales) Regulations 2007 came into effect on 1 August 2007 as part of a phased
approach. The first stage required the production of energy performance certificates
for homes when sold (marketed sales only), moving to all buildings when built, sold, or
newly rented by 2008.
• The domestic EPC was introduced as a cost-based metric. The A to G rating simply
shows how cheap or expensive a home might be to run, based on a standard
occupancy model. But nothing more.
• Elmhurst has been calling for changes to the EPC since 2019. Reform has been on the
cards since a call for evidence on EPCs in 2018, followed by the government’s EPC
Action Plan in 2020.
• In England and Wales, the Government Department for Levelling Up Housing and
Communities (DLUHC) has indicated the EPC Reform consultation will come out this
year, and the Department for Energy Security and Net Zero (DESNZ) has indicated its
‘EPC Wrapper’ consultation will also arrive in 2024/25 as the results of the Home
Energy Model (HEM) – the new methodology to replace SAP. A consultation should
be out in 2024.

No. Having about 16 years of asset rating data about our housing stock is hugely
valuable and we shouldn’t stop collecting that information. Having even a basic EPC
regime in place is better than making no attempt to measure building energy
performance. Leaving the UK without a framework would be disastrous in our
roadmap to Net Zero 2050.
• That said, it’s clear that public expectations of energy assessments are much higher
than the current EPC regime can deliver. They need adding to, rather than scrapping
altogether. Maybe give them a new name too. This has been recognised for many
years – we hope the new government will see through the well-documented plans for
EPC reform.
• We strongly support this vital industry. The importance of the EPC has significantly
increased, and we welcome the updated methodologies. The reform of the EPC is
urgently needed to clarify many issues raised by consumers.
• We are committed to helping consumers understand their homes and buildings and
provide information on what to do next to make them more energy efficient. It is
essential that we measure homes correctly and accurately, empowering consumers
with the confidence to take the next steps in reducing energy usage and carbon
emissions, lowering bills, and living in warmer, healthier homes.