EPCs: What are they, and why do they matter?

Christopher McFadden
Written By
Roland Ellison editor of The Eco Experts
Reviewed By
Updated on 17 April 2024
  • You need an EPC to build, sell or rent a property
  • They provide a simple overview of the property’s energy efficiency
  • Only accredited assessors are allowed to create EPCs
  • Check an EPC before buying, selling or renting a property

If you want to go green but can’t afford to pay the initial costs of solar panels or a heat pump, you can still significantly increase the energy efficiency of your home by improving its Energy Performance Certificate (EPC).

Whether you’re a homeowner, renter, landlord, or tenant, it’s important to know what an EPC is. First introduced in 2007, EPCs are now legally required for a building to be sold, let, or built — but what exactly are they?

In this guide, we’ll cover everything you need to know about EPCs, including how they work, what they include, who needs one, and how to get one.

Someone looking at EPC

An EPC has one main purpose: to show how energy-efficient a building is and, by proxy, how much it will cost to occupy it. The main thrust of the rating for domestic EPCs is to give a rough idea of the energy costs per year.

It should be noted that a commercial EPC is more tailored to providing overall energy efficiency/carbon dioxide emissions only.

Therefore, the rating of each EPC type is tailored to reflect this. A similar rating, say a “C,” for a home will not necessarily mean it is as energy efficient as a shop with a “C” rating.

The format of an EPC will vary depending on the type (for a house or commercial property) and when it was created. Generally speaking, it will include the same basic information in a different order.

An EPC provides a rating from A to G, with ‘A’ being very efficient and ‘G’ being inefficient. The certificate also tells you how expensive it will be to heat and light the property, and how high the building’s carbon dioxide emissions will be.

Below the overall rating, you’ll find recommendations on reducing energy and saving money around the building.

Remember that any figures on an EPC are not tailored to you, your housemates, or your lifestyle – instead, they will be targeted at a ‘typical’ household in that property.

If you implement any of the recommendations outlined in the EPC, it’s worth getting a new certificate to include these improvements if you are looking to rent or sell your property.

To calculate which energy-efficiency band a house falls under, an approved domestic energy assessor will visit your home to see how its internal heat, hot water, and lighting are generated.

The assessment will also look at the property’s size (to find its internal air volume) and use (i.e., the number of “living spaces” there) and how the building is constructed (walls, floors, roofs, insulation, windows, etc.).

This process includes looking at the efficiency of the heating and water systems, checking for insulation throughout the property, and searching for features like double glazing and energy-efficient light bulbs around the house.

It is a bit more in-depth than that, but this is why the assessor will poke around places you might not expect (like the attic) and make random measurements of the walls.

Following the site inspection, all site information will be plugged into specially designed software (Reduced Standard Assessment Procedure, or rdSAP), which will pump out the assessment results.

Note that the assessor may request specific information on-site or after to help make the assessment as accurate as possible.

This may include installation certificates for things like solar panels, insulation, or boilers or evidence of the age of certain things like windows, etc.

If unavailable, the assessor will be required to use the default “assumed” values for a building of the same construction and age.

It is important to remember that the software will also make assumptions about the building’s occupancy.

This is “baked” into the software on purpose to enable it to provide a “benchmark” for your home to a pretend “perfect world” proxy of your home.

The rating, therefore, can be seen as a “rough guide” rather than an accurate assessment of your home in particular. This is the case for all homes ever assessed using the EPC software.

Once all that has been compiled, the software will then generate an overall rating which will fall between the following bands:

  • 92-100 points = EPC rating A
  • 81-91 points = EPC rating B
  • 69-80 points = EPC rating C
  • 55-68 points = EPC rating D
  • 39-54 points = EPC rating E
  • 21-38 points = EPC rating F
  • 1-20 points = EPC rating G
Example of an EPC

An example of an Energy Performance Certificate (EPC) rating graph. This is the older format, but newer ones are very similar. 

Yes, every property must have an EPC – the certificate needs to be available to potential buyers as soon as you put your property on the market.

An EPC is required by law in the commercial and residential sectors and is subject to increasingly strict guidelines. Legally, an approved domestic energy assessor must also provide the certificate.

Not only do you need an EPC, but you need to have a good rating on it, too.

The Minimum Energy Efficiency Standards (MEES) (or Minimum EPC rating), which came into effect in April 2018, mandate that landlords with an EPC rating of ‘F’ or ‘G’ won’t be able to renew existing leases until they improve the property to a minimum of ‘E.’

This MEES rating will be raised over time, so it is good practice for landlords to get ahead of the game when they can.

This new standard now applies to all tenancies (since 1st April 2020), and the UK government’s Future Homes Standard is set to come into play in 2025, which may also increase the minimum EPC rating for homes in the UK.

Did You Know

In Scotland, you must display the EPC somewhere in your property, such as in the meter cupboard or next to the boiler.

Yes, all landlords are legally required to secure an EPC for any property they own.

If a landlord fails to provide an EPC, they risk being fined quite a hefty sum.

However, this is usually enforced by letting agents or solicitors during the sales process, so the chances of this happening are very low.

Below, we’ve outlined the price of an EPC compared to the cost of getting fined for not having one or having one below the minimum requirements:

EPC procedureAverage cost
EPC£35-£120
Fine for failing to get an EPC£200
Maximum cost of bringing your property to band E£3,500
Fine for failing to bring your property to band E£4,000

Data from Checkatrade

In short, yes. In the UK, the requirement for an EPC for commercial buildings generally applies to all buildings that are sold or rented out. However, specific size and usage criteria mean that some buildings are exempt from requiring an EPC.

The general rule is that commercial buildings with a total useful floor area of more than 50 square meters need an EPC when built, sold, or rented. However, smaller buildings (under 50 square meters) might also require an EPC under certain conditions, such as if they are part of a larger building being sold or rented.

There are exemptions to this, but in most cases, an EPC will likely be needed if the site is heated or has lighting or hot water.

Once you attempt to commission an accredited assessor, they will make this all very clear before you fork out for something you don’t need.

While not technically ‘commercial’ buildings, public buildings also need an EPC, called a Display Energy Certificate (DEC), but this is outside the scope of this guide.

As mentioned, an EPC is required if property is to be sold or rented, but before you pay to get one done, you should check to see if a valid one already exists for your property.

Since the last major format update, EPCs have generally been only available online. Still, your energy assessor may (at their discretion or the EPC payer’s request) provide a PDF version.

Whatever the case, the EPC for a house or a commercial building (technically called a non-domestic property) is publicly available and searchable via the official UK Government portal (or the Scottish equivalent).

Check here first. If it has expired or doesn’t exist, you should commission an accredited energy assessor to complete one for you.

In the UK, only accredited domestic energy assessors can produce valid EPCs. The above portal also has a handy search function for local assessors near you.

Like anything, you should get quotes from several local assessors to make sure you get the best value for money.

Be ready for a wide range of prices depending on the assessor’s workload. The busier they are, the higher the price is likely to be.

That being said, here is a list of sources to find approved assessors.

How can you find an approved assessor?

If you’re selling your home through an agent, it is also a good idea to ask them to arrange a Home Report, including an energy report and EPC.

This is not a legal requirement but adds valuable information for potential buyers. In Scotland, however, you have no choice.

Typically, the cost of an EPC can be anywhere between £35-£120, depending on a few things, including:

  • The size of your house
  • The area where you live (for example, London will be more expensive than rural areas)
  • The type of property you live in
  • The number of bedrooms in your property
  • How busy and how far away the potential assessor is. This is the case for any tradesman or professional building assessor.

EPC costs also vary between individual assessors, so it’s a good idea to compare quotes and ensure you’re getting the best deal.

However, the more experienced, reliable, and trustworthy energy assessors will come at a premium. This is more important than you might think, so use referrals from happy customers.

It’s also important to remember that if tenants or potential buyers ask to see the EPC rating, you’re obligated to show it to them free of charge.

An EPC rating is valid for 10 years. Once the decade is up, you’re legally required to get a new one.

This is to ensure that buyers and renters can get an accurate, up-to-date reading of how energy-efficient the property is.

  • An EPC is needed whenever a property is rented or sold in the United Kingdom.
  • Check if your home has a valid EPC, and if not, find an energy assessor to complete one for you.
  • Getting an EPC is a walk in the park – once you get in touch with an approved assessor, you can put your feet up and let them do the hard work.
  • If you end up with a rating below what you were hoping for, fear not – there are things you can do to improve it. This may include finding missing information the assessor has requested, or you can try introducing a few energy-saving features to your home. However, note that a new EPC must be generated if you do this (which will cost you), so change older bulbs with newer energy-efficient LED bulbs before the assessor comes to your home.
  • If you want to get a head start on this, check out our Eco Home Hub, where you can find various useful articles to help you.

Written by

Christopher McFadden

Christopher is an Environment, Health & Safety (EHS) specialist with extensive experience advising consumer and trade clients on energy efficiency and sustainability. With a Master's in Earth Sciences from Cardiff University, Christopher has attained professional energy and sustainability auditing qualifications and various postgraduate certificates and diplomas. He is a qualified and accredited Level 3 and Level 4 non-domestic and domestic energy assessor, a Green Deal assessor, and a Practitioner member of the Institute of Environmental Management and Assessment (IEMA). He also recently qualified as a level 5 Retrofit coordinator. In addition to his day job, Christopher has also honed his skills as a STEM writer for several well-known online publishers, sharing his knowledge and passion for science, engineering, and dinosaurs with millions of readers around the world.

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Reviewed By

Roland Ellison editor of The Eco Experts

Roland Ellison is a London-based journalist and content producer who joined The Eco Experts as Editor in November 2023. He is passionate about solar power, reducing plastic waste, and technology that can help humanity overcome some of its greatest challenges.

Having started his editorial career in business-to-business print journalism in the construction sector, Roland has gone on to lead teams in the production of digital and video content at The Daily Mirror, BBC Global News, and at Storyful (part of News Corp).

As a journalist, he has written extensively about science, engineering, sustainability, personal finance, travel, sport, music, and entertainment for consumer audiences around the world.

With a BA in History from the University of Leeds, Roland lives with his wife, two children, and two cats in South London. He is a keen cyclist, music and film fanatic who enjoys playing and watching sport - particularly his local team, Crystal Palace FC.

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