EPC Certificate and Why They Matter

An Energy Performance Certificate shows a property’s expected energy efficiency and is legally required for most homes marketed for sale. Find out what buyers should check during conveyancing.

Published: 2026-07-12

Last updated: 2026-07-13

Published by KnowNow Property Guidance

What Is an EPC and What Does It Mean in Conveyancing?

An Energy Performance Certificate, usually called an **EPC**, provides an assessment of a property’s energy efficiency.

It gives the property a rating from **A to G**, with A representing the highest level of energy efficiency and G the lowest.

The certificate also records information about the property’s construction, heating, insulation and estimated energy use. It may recommend improvements that could increase the rating or reduce energy costs.

An EPC is not simply optional information prepared for interested buyers. For most homes in England and Wales, the law requires the seller to commission an EPC before the property is marketed for sale.

Does a property need an EPC before it can be sold?

In most cases, yes.

The seller must normally have commissioned an EPC before marketing the property. If a valid certificate already exists, a new assessment may not be needed.

An EPC is normally valid for ten years unless a newer certificate is produced.

The seller or estate agent must make the certificate available to prospective buyers. The energy rating will also usually appear within the property listing.

There are limited exemptions for certain types of building, so the absence of an EPC does not always mean the seller has failed to meet the legal requirements.

What information does an EPC contain?

An EPC will normally include:

• the property’s current energy-efficiency rating
• its potential rating if recommended improvements are completed
• estimated energy use and typical costs
• information about heating and hot-water systems
• details of insulation, windows and lighting
• suggested energy-efficiency improvements
• an estimate of the possible cost and benefit of each improvement
• the date the certificate was issued

The assessment is based on the property’s construction and installed features rather than the current occupants’ actual energy use.

What role does the EPC play in conveyancing?

The EPC gives the buyer information about the property before the transaction completes.

During conveyancing, the buyer and their conveyancer may consider:

• whether a valid EPC is available
• whether the certificate appears to relate to the correct property
• how old the certificate is
• whether the property has changed since it was assessed
• whether any unusual energy arrangements are mentioned
• whether the buyer has concerns about heating or efficiency
• whether recommended improvements could require consent

The EPC does not prove ownership, confirm planning permission or replace the legal searches. It is supporting information about the building’s expected energy performance.

The buyer’s conveyancer would not usually decide whether the property is suitable based on the rating alone. However, information within the EPC may prompt the buyer to raise further questions.

Can a home with a low EPC rating still be sold?

Yes.

For an ordinary owner-occupied residential sale, the requirement is generally to provide a valid EPC. The property does not normally need to achieve a particular minimum rating before it can be sold.

A property with an E, F or G rating can still be marketed and transferred.

A lower rating may nevertheless affect the buyer’s view of:

• expected heating costs
• future improvement work
• comfort and heat retention
• suitability for certain mortgage products
• the property’s longer-term attractiveness

Different rules can apply to rented properties, so buyers purchasing as landlords may need to consider the rental requirements separately.

What do the EPC ratings mean?

EPC ratings are grouped into bands:

• **A and B:** very energy efficient
• **C:** relatively energy efficient
• **D:** a common rating for many existing homes
• **E, F and G:** lower energy efficiency

A lower rating may indicate that the property loses more heat, uses less efficient heating or has fewer energy-saving features.

However, the rating should be considered alongside the property’s age, size, construction and condition.

An older home may naturally perform differently from a recently built property without necessarily being defective.

Does the EPC show the actual energy bills?

No.

The costs shown on an EPC are estimates based on standard assumptions.

Actual bills may differ depending on:

• how many people occupy the property
• how often the heating is used
• the preferred indoor temperature
• energy tariffs and prices
• hot-water use
• whether the whole property is heated
• how efficiently the systems are operated

The seller’s recent bills may provide additional context, although their usage could be very different from yours.

Does a low EPC rating mean the property is in poor condition?

Not necessarily.

A lower rating does **not** automatically mean:

• the property is structurally defective
• the heating system is broken
• the property cannot be sold
• every recommended improvement is essential
• the home is unsuitable to buy
• the estimated costs will be exact

The EPC assesses energy performance. It is not a structural survey or a detailed inspection of the building’s condition.

A surveyor may identify physical issues that do not appear within the EPC.

What are the recommended improvements?

The certificate may recommend measures such as:

• adding loft or wall insulation
• improving hot-water insulation
• installing more efficient heating
• upgrading windows
• adding heating controls
• fitting low-energy lighting
• considering renewable-energy technology

These are recommendations rather than legal instructions to the buyer.

Not every improvement will be practical, suitable or cost-effective. Some work may also need planning permission, building-regulation approval, listed-building consent or another form of permission.

Could the EPC be outdated?

Yes.

An EPC reflects the property as it was assessed on a particular date.

Since then:

• the boiler may have been replaced
• insulation may have been added
• windows may have been upgraded
• an extension may have been built
• the heating system may have changed
• solar panels or other technology may have been installed

If the certificate is several years old, it may not fully reflect the property as it appears when you buy it.

You can ask the seller whether any relevant improvements have been completed since the assessment.

What if there is no EPC?

The first step is to check whether a valid certificate already exists under a slightly different version of the address.

Where no valid EPC exists and no exemption applies, the seller will normally need to arrange one.

Its absence does not usually determine the legal title to the property, but it may indicate that the marketing requirements have not yet been fully met.

The buyer can ask the estate agent or conveyancer to clarify the position.

What should you consider before buying?

When reviewing the EPC, you may wish to consider:

• the current and potential ratings
• the date of the certificate
• the property’s main heating system
• the insulation and glazing recorded
• the estimated cost of suggested improvements
• whether work has taken place since the assessment
• whether recommendations would suit the property
• whether any proposed improvements require permission
• whether the expected energy performance fits your budget

The EPC is most useful when considered alongside your viewing, survey, conveyancing documents and expected use of the home.

Is a low EPC rating a reason not to buy?

Not by itself.

A less efficient property may cost more to heat or benefit from future improvements, but it could still be suitable for you.

Some buyers may be comfortable making gradual upgrades. Others may prefer a home that is already more efficient.

The important point is understanding the likely energy performance and allowing for any improvements you may wish to make.

How KnowNow can help

KnowNow can present available EPC information for a property, including its current and potential ratings, certificate date and recorded energy features.

The Signal Pack places this alongside other property information, helping you understand both the home itself and the matters likely to appear during the wider buying and conveyancing process.

It provides early context and does not replace the official EPC, property survey, legal advice or professional energy assessment.

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