If you are buying a new-build home in England or Wales, the completed property will generally need an Energy Performance Certificate, usually known as an EPC.
In most cases, the person carrying out the building work must give the EPC to the property owner no later than five days after the work has been completed. The certificate shows the home’s calculated energy efficiency, gives it a rating from A to G and provides information that can help you compare it with other properties.
This guide covers new-build homes in England and Wales. Different energy certificate arrangements apply in Scotland and Northern Ireland.
What is an Energy Performance Certificate?
An Energy Performance Certificate shows the calculated energy efficiency of a property. It gives the property a rating from A, the most energy-efficient, to G, the least energy-efficient.
The assessment considers elements such as the property’s construction, insulation, glazing, ventilation, heating, hot water, fixed lighting and any renewable or low-carbon technology.
An EPC also provides information about the property’s estimated energy use and carbon dioxide emissions. It may recommend measures that could improve its calculated energy performance.
An EPC is valid for up to 10 years, unless a newer EPC for the property is registered during that period. Check the issue and expiry dates shown on the certificate.
Do new-build homes need an EPC?
Yes, in most cases. GOV.UK guidance states that an EPC is required when a property is newly constructed, sold or let.
For a newly constructed home, the person carrying out the building work must give the EPC to the owner no later than five days after the building work has been completed.
If you reserve a home before construction is finished, an EPC for the completed property may not yet be available. The developer may be able to provide energy information based on the planned design and specification, but this is not the registered EPC for the completed home.
If the registered EPC is not available, you may wish to ask the sales team:
- whether the available energy rating is based on the planned design or the completed home
- when the registered EPC is expected to be available
- how you will be able to access the certificate
- whether any specification changes could affect the rating
Once the EPC has been registered, you can use the GOV.UK find an energy certificate service to view and download it free of charge.
What does an EPC show?
The information can vary according to the property and certificate. A domestic EPC may show:
- Current energy-efficiency rating: The home’s calculated rating from A to G.
- Potential rating: The rating the property could achieve if specified improvements were completed.
- Estimated energy use and costs: Figures calculated using standard assumptions rather than the circumstances of a particular household.
- Energy-related features: Information about elements such as the walls, roof, windows, heating, hot water and lighting.
- Recommended measures: Changes that may improve the property’s calculated energy performance.
- Carbon dioxide emissions: Emissions associated with the property’s calculated energy use.
- Certificate details: Information such as the certificate reference, issue date, expiry date and accredited assessor.
An EPC does not predict your energy bills. Its figures are based on standard assumptions. What you pay will depend on factors such as energy prices, the number of people in your household and how you use heating, hot water and electricity.
How is a new-build EPC rating calculated?
New homes are assessed using the government-approved methodology in force at the time of the assessment.
As of September 2026, SAP 10.3 is the sole approved methodology for assessing the energy performance of homes. SAP is used to generate EPCs and to assess new homes against the relevant energy-performance requirements in the Building Regulations.
The assessment uses information about the home’s construction and fixed services. This can include its insulation, glazing, ventilation, heating, hot-water systems, fixed lighting and any renewable or low-carbon technology.
The government intends to introduce the Home Energy Model alongside SAP 10.3 for relevant Future Homes Standard assessments. The Home Energy Model is ultimately intended to replace SAP for the energy rating of dwellings.
You can check the latest GOV.UK guidance on the Standard Assessment Procedure for the current position.
An EPC measures calculated energy performance under standard conditions. It does not measure every aspect of a home’s environmental impact or represent its complete carbon footprint.
EPC ratings for new-build homes
A is the highest EPC band, followed by B. The rating for an individual home depends on the information used in its assessment, including its construction, heating system and other energy-related features.
In its 2025 analysis, the Office for National Statistics reported a median EPC score of 84, equivalent to Band B, for new dwellings in England and a median score of 84 for new dwellings in Wales during the five-year period to March 2025.
In these statistics, “new dwellings” includes newly built homes, conversions and homes created through a change of use. The figures do not apply exclusively to properties built entirely from new and do not mean that every new-build home will receive a Band B rating.
Two homes in the same EPC band can have different heating systems, specifications and estimated energy needs. The EPC rating is useful for comparison, but it should not be considered on its own.
Why does an EPC rating matter when buying a new home?
An EPC provides a standard way to compare the calculated energy performance of different properties.
A higher rating represents better calculated energy performance under the assumptions used for the assessment. It does not guarantee a particular level of energy use or a specific household bill.
When comparing homes, consider the EPC rating alongside:
- the type of heating and hot-water system
- insulation and glazing
- heating controls and thermostats
- ventilation and how it is controlled
- any solar panels, heat pumps or other low-carbon technology
- the specification for the individual property
Features can vary between properties and developments. Check the specification for the home you are considering rather than assuming the same features are included across every new-build development.
Find out more about buying a new-build home.
What can you check on a new-build EPC?
These checks can help you understand the EPC for a property. They are not a complete list of the legal, financial or practical checks involved in buying a home.
- Check the address. Make sure the EPC relates to the exact plot, house or apartment you are considering.
- Review the rating. Compare it with any energy rating or related information supplied before the property was completed.
- Read the recorded features. Compare the energy-related features shown on the EPC with the information supplied for the home.
- Read the recommendations. Check whether the assessor identified any measures that could improve the calculated rating.
- Check the dates. Review the certificate’s issue and expiry dates.
An EPC is not a survey or a complete record of the property’s specification. It should be considered alongside the property specification, warranty documents, legal information and any professional advice obtained as part of the purchase.
If the registered EPC differs from information supplied earlier, ask the sales team what has changed and which information applies to the completed home. If the difference could affect your decision to buy, consider raising it with your conveyancer or another suitably qualified independent professional.
Can a new-build EPC rating change?
Yes. An EPC records the property’s calculated energy performance when the assessment is completed.
A later assessment may produce a different rating if changes are made to the property, its heating or hot-water system is replaced, energy-related features are installed, more accurate information becomes available or the approved assessment method changes.
An EPC does not update automatically after work is completed. The property must be assessed again for a new certificate and rating to be produced. If a newer EPC is registered, the earlier certificate is no longer valid for the purposes covered by the regulations.
How can you find a new-build property’s EPC?
Use the GOV.UK find an energy certificate service to search for a property’s registered EPC.
The service allows you to check the recorded rating and expiry date, read the available energy information and download the certificate free of charge.
If you cannot find a newly constructed property, ask the developer or sales team whether its EPC has been lodged. The property may not appear on the register until its assessment has been completed and the certificate registered.
Ready to find a home? Explore the new-build homes available through Guinness Homes and visit individual development pages for information about the homes and buying options available.
This article provides general information about Energy Performance Certificates for new-build homes in England and Wales and is not legal advice. Requirements and assessment methods can change. Check the latest GOV.UK guidance and the information supplied for the individual property. If you are unsure how the requirements apply to your circumstances, seek advice from a suitably qualified independent professional.
