What Will Fail an EPC?

Energy Performance Certificates (EPCs) are a vital part of property compliance in the UK, especially for landlords, commercial property owners, and developers. But one of the most common questions we hear is: what can actually fail an EPC?

The answer is a little more nuanced than a simple pass/fail — so let’s break it down.

EPCs don’t technically “Fail”, but they can make your property non-compliant and render a transaction unlawful

Here’s the key thing: an EPC itself doesn’t issue a pass or fail. Instead, it provides a rating or grade from A (most efficient) to G (least efficient), along with recommendations to improve energy efficiency.

Under current UK legislation, certain EPC ratings can make a property non-compliant with legal requirements — especially under the Minimum Energy Efficiency Standards (MEES).

The legal minimum EPC rating

For commercial and residential leased properties, the minimum EPC rating is currently E.

If your building scores an F or G, it will be considered “sub-standard” under MEES regulations — meaning:

• It cannot be legally let unless it qualifies for an exemption.

• You could face penalties of up to £150,000 for non-compliance.

So, while it’s not a “fail” in the certificate, it definitely can be a fail in the eyes of the law and you need to avoid falling foul of regulations, this is something normally picked up by each side's legal representatives in a commercial property deal. We also advise looking at where regulations are headed particularly if your lease looks set to run over one of the forthcoming milestones as the minimum ratings are upgraded over the coming years:-

Common Reasons Properties Score Poorly on EPCs

1. Poor insulation

Inadequate roof, wall, or floor insulation is one of the biggest contributors to heat loss and a guaranteed way to drop your EPC rating. If you have had insulation installed but it is not currently visible (perhaps it's behind plasterboard walls) its vital you try and source some evidence of it's installation, photos during a refurbishment or detailed invoices from a fit out company for example.

2. Outdated heating systems

Old and inefficient Systems fuelled by natural gas are heavily penalised by the metrics behind EPCs so if at all possible you should try and seek electric alternatives for space heating and hot water systems. Air Source heat pumps manufactured in the last few years are highly efficient and give a substantial boost to commercial EPC scores. A lack of heating controls like thermostatic radiator valves (TRVs) or smart programming systems for more advanced air conditioning systems all negatively impact your score.

3. Single glazed windows

If your property still has single glazing or draughty frames, it's almost certainly losing heat - and EPC points, there really is no excuse in this day and age not to have double or secondary glazing, ideally with low-emissivity (Low-e) coating

4. Lack of low-energy lighting and controls

Inefficient lighting can drag down your score particularly as the scale of a building increases - a 20,000 square foot office will see a dramatic difference between different lighting types as opposed to a small retail unit. EPCs now heavily favour the use of LED lighting or at the very least compact fluorescent lighting throughout the building. PIR or Passive Infrared lighting controls which can sense human presence can also be extremely beneficial to EPC results - there's no point in having even the most efficient lighting if it's left switched on in an empty room!

5. No renewable technologies

Properties with no solar panels, heat pumps, wind turbines or other renewable technologies miss out on valuable EPC credits, the metrics significantly reward the presence of these systems.