Common EPC Mistakes That Delay Property Sales and Rentals in the UK

An Energy Performance Certificate (EPC) is a legal requirement for most property sales and lettings in the UK. Despite this, EPC-related issues remain one of the most common causes of delays during property transactions.

Many of these delays are avoidable. Below are the EPC mistakes that most frequently cause problems for sellers, landlords and estate agents.

Mistake 1: Assuming an Old EPC Is Still Valid

EPCs are valid for 10 years. A certificate issued in 2016, for example, will expire at some point in 2026.

One of the most common issues occurs when a property owner assumes an EPC is still valid, only to discover it has expired once marketing begins.

For a full explanation of EPC expiry dates, see our guide on when EPCs expire and when a new one is needed.

Mistake 2: Leaving the EPC Until After Marketing Starts

These issues are most common in active property markets where homes are listed quickly and compliance checks happen later in the process. We regularly see EPC delays affecting sales and rentals in cities such as Hull and Belfast, where older housing stock and high transaction volumes increase the risk of last-minute EPC problems.

Legally, a valid EPC must be available at the point of marketing. This applies whether a property is being sold or let.

Delays often occur when:

• An EPC is booked after photos or listings go live
• The certificate expires during marketing
• An assessor cannot attend quickly

In busy markets, this can pause listings and frustrate buyers or tenants.

Mistake 3: Assuming EPCs Are Only a Tick-Box Requirement

While EPCs are a legal requirement, they can also influence buyer and tenant behaviour.

Nationally, EPC ratings are increasingly linked to buyer confidence, rental demand and pricing discussions. This trend is explored in more detail in our article on how EPC ratings affect house prices, rentals and buyer demand.

Ignoring this can lead to unexpected questions or negotiations later in the process.

Mistake 4: Forgetting That Improvements Can Change the EPC

If a property has been upgraded since the last EPC was issued, the certificate may no longer reflect its true performance.

This often applies where owners have:

• Installed a new boiler
• Added insulation
• Replaced windows or doors
• Extended the property

In these cases, relying on an old EPC may understate the property’s efficiency.

Mistake 5: Not Understanding EPC Costs in Advance

Uncertainty around EPC pricing can also delay bookings. Costs vary depending on property size, layout and complexity.

For a breakdown of typical EPC costs across the UK, see our guide on how much an EPC costs in the UK.

Mistake 6: Assuming EPC Rules Are the Same for Selling and Letting

While EPCs are required for both sales and rentals, landlords also need to ensure the property meets minimum energy efficiency standards.

Failing to meet these requirements can prevent a property from being legally let, even if an EPC exists.

How to Avoid EPC-Related Delays

Most EPC delays can be avoided by:

• Checking EPC validity early
• Booking assessments in advance
• Updating EPCs after major improvements
• Understanding legal requirements before marketing

Booking an EPC

If you need a new EPC or are unsure whether your current certificate is valid, arranging an assessment early helps prevent unnecessary delays.

EPC assessments can be arranged online via the booking page.

Conclusion

EPC delays are rarely caused by the assessment itself. More often, they result from misunderstandings around expiry, timing and legal requirements. Addressing these issues early helps keep property transactions moving smoothly.