What to do if your commercial EPC looks wrong
Updated 19 October 2026 · SEO Dons Editorial
If a commercial EPC looks wrong, check the certificate's details on the GOV.UK register against the building first, then raise specific errors, with evidence, with the assessor named on the certificate. If that does not resolve it, contact the assessor's accreditation scheme, which is also named on the certificate and must have a process for resolving complaints. A lodged EPC cannot be edited, so a correction or a fresh assessment means a new certificate, and the most recent lodged EPC is the valid one.
What should you check first?
Find the certificate on the GOV.UK register, which can be searched by postcode, street name and town, or certificate number. The certificate reference number lets you confirm you are looking at the genuine lodged version, and the register's page for each certificate has a section for other certificates for the same property. If more than one is less than 10 years old, only the most recent is valid.
Then compare the details with the building:
| Field on the register | What to compare it with | Why it matters |
|---|---|---|
| Address and building part | The unit, floor or building being sold or let | A certificate for a different part of the building does not cover the space in the transaction |
| Property type | How the building is actually used | Each activity carries standard assumptions for occupancy, temperature, lighting and hot water |
| Total floor area | Measured survey or lease plans | The rating is adjusted for total useful floor area |
| Main heating fuel and building environment | The heating system, and whether there is air conditioning or mechanical ventilation | The rating is a carbon-based index, so fuel and systems drive the result |
| Assessment level | How complex the building's services are | The assessor must be accredited for the category of building |
| Date of assessment and date of certificate | When any works were completed | Improvements made after the survey are not in the rating |
Read the recommendation report too. A recommendation to add something the building already has, such as time control on the heating, usually points to an input that was missed. The search itself is covered in how to find a commercial EPC on the register.
Is it an error, or the method working as designed?
Some results that look wrong are the method doing what it is meant to do. A commercial EPC is an asset rating for a standardised use of the building, so low bills, short opening hours or careful energy management do not show up in it. That is not an error. How commercial EPC ratings are worked out explains why.
Other results reflect the rules assessors must follow when evidence is missing. The Non Domestic EPC Conventions for England and Wales, which accreditation schemes issue to their assessors, set cautious assumptions in several places. T8 fluorescent tubes are treated as low-frequency unless there is evidence otherwise. Empty light fittings are entered as CFL where the fitting will take one, or otherwise as the least efficient lamp type it can hold. Where plant cannot be inspected and specific details are not available, it is modelled on a worst-case basis for the type believed to be present. The assessor is also not responsible for establishing the official planning use class: unless it is provided from a suitable source, the building type is based on the assessor's visual assessment on the day.
In those cases the fix is evidence rather than a complaint. Documents can be used where there is a demonstrable link between what was seen on site and the paperwork, such as a model number that matches a data sheet. Design-stage documents alone are not acceptable; as-built documents are.
How do you raise it with the assessor?
The register tells you where to start: if you are unhappy about the assessment or certificate, you can complain to the assessor who created it. The assessor's contact details are on the certificate. Set the problem out precisely:
- the certificate number and the address exactly as shown on the register
- each field or assumption you believe is wrong, and what it should say
- the evidence for each point, such as as-built drawings, data sheets, commissioning certificates, invoices or photographs showing model numbers
Assessors carry legal responsibilities. Under the 2012 Regulations they must carry out energy assessments with reasonable care and skill, and the government guide describes that duty of care as owed both to the seller or prospective landlord and to the prospective buyer or tenant. The guide also says the assessor must validate information through a site inspection, and that remote lodgement, where a certificate is lodged from data the assessor has not collected or verified, is not acceptable.
What if the assessor does not resolve it?
The next step is the assessor's accreditation scheme, also named on the certificate. Every energy assessor must be a member of a scheme approved by the Secretary of State, and before approving one the Secretary of State must be satisfied that it makes adequate provision for consistent, accurate and independent assessments and for facilitating the resolution of complaints against its members.
The government guide to EPCs for non-dwellings describes what should follow:
- the scheme must investigate the complaint and, where necessary, provide appropriate redress
- where the information on the EPC is found to be incorrect, a new report must be issued and the information on the register amended
- if the complaint cannot be resolved, the scheme refers it to an independent third party for adjudication
- a disputed EPC can be annotated on the register to show it is under investigation, which only the assessor's scheme can do
That guide is several years old, so check the scheme's own current procedure. Schemes publish their own routes. Elmhurst, for example, describes itself as a government-approved accreditation body that carries out compliance checks on its members' certificates throughout the year, and takes complaints through an online complaints resolution form.
Two other routes cover different problems. Complaints about whether an EPC was available, or valid, when a building was marketed for sale or rent go to the local weights and measures authority, usually trading standards. If an EPC is alleged to have been produced fraudulently, the guide says that is a criminal matter to be reported to the police.
When is commissioning a new EPC the better route?
Sometimes the most reliable fix is a new certificate: when the building has changed since the survey, when the evidence needed was not available at the time, or when you have lost confidence in the original assessment. A new EPC can be produced by any energy assessor who is accredited for that category of building.
Understand how validity works before you commission one. Under the 2012 Regulations an EPC is only valid if it was entered on the register no more than 10 years before it is made available, and no other EPC for the building has been entered since. In other words, the latest lodged EPC is the valid one, whatever its rating. A new certificate is a fresh assessment, not an appeal, and it replaces the old one even if the result is worse.
Give the new assessor the old certificate number and the evidence you have gathered, so the same gaps are not repeated. You can request quotes for a new assessment through this site's form, and the enquiry is passed to companies that carry out commercial EPCs.
What does a wrong EPC mean for letting?
For landlords the stakes are practical. In England and Wales, a non-domestic property below EPC E cannot be let on a new, extended or renewed tenancy without a registered exemption, which has been the rule since 1 April 2018, and since 1 April 2023 continuing an existing letting below that line is a breach as well. An EPC that wrongly shows F or G needs resolving before a letting decision rests on it. A compliance notice can later ask for the EPC that was valid when the property was let, so keep copies of each certificate and of any correspondence about it. The rules, exemptions and penalties are set out on the MEES compliance page.
Sources
- Find an energy certificate, GOV.UK register (search page, plus the standard wording shown on non-domestic EPC and recommendation report pages), checked 19 October 2026.
- A guide to Energy Performance Certificates for the construction, sale and let of non-dwellings, Ministry of Housing, Communities and Local Government (GOV.UK), checked 19 October 2026.
- The Energy Performance of Buildings (England and Wales) Regulations 2012, regulation 2, legislation.gov.uk, checked 19 October 2026.
- The Energy Performance of Buildings (England and Wales) Regulations 2012, regulation 9, legislation.gov.uk, checked 19 October 2026.
- The Energy Performance of Buildings (England and Wales) Regulations 2012, regulation 22, legislation.gov.uk, checked 19 October 2026.
- The Energy Performance of Buildings (England and Wales) Regulations 2012, regulation 24, legislation.gov.uk, checked 19 October 2026.
- Non Domestic EPC Conventions for England and Wales, Issue 9, NDEPC Conventions Group, published on uk-ncm.org.uk, checked 19 October 2026.
- Complaints Resolution, Elmhurst Energy (government-approved accreditation scheme), checked 19 October 2026.
- Non-domestic private rented property: minimum energy efficiency standard - landlord guidance, Department for Energy Security and Net Zero (GOV.UK), checked 19 October 2026.
Common questions
Can the assessor simply edit the certificate on the register?
No. Once an EPC is registered it cannot be altered. A disputed EPC can be annotated as under investigation by the assessor's accreditation scheme, and a corrected result means a new certificate being lodged.
Will a new EPC replace an old one with a better rating?
Yes. An EPC stops being valid once another EPC for the building is lodged, so the newest certificate applies even if its rating is lower. It is worth resolving data errors with evidence before commissioning a fresh assessment.
Can a tenant or buyer complain about an EPC?
Yes. The assessor's duty of care can be enforced by any prospective or actual buyer or tenant while the certificate is valid, as well as by the seller or landlord. The complaints route is the same: the assessor first, then their accreditation scheme.
The energy bills are low but the EPC is poor. Is the EPC wrong?
Not necessarily. A commercial EPC is an asset rating based on a standardised use of the building, so actual consumption is not an input. Check the recorded fabric, systems, floor area and activities instead.
Where are the assessor's and the scheme's contact details?
On the certificate. The government guide confirms that contact details for both the assessor and the accreditation scheme can be found on the EPC, and the register shows them under who to contact about the certificate.