Improve EPC Rating - Is It Worth It?
You look at your Energy Performance Certificate [EPC] and see a big D staring back at you. Underneath, it tells you that your home could potentially become a B.
So, if you're thinking of selling, should you spend money getting it there?
Perhaps. But a better EPC rating doesn't automatically mean you've made a good investment. Some improvements can make your home warmer, cheaper to run and potentially more attractive to buyers. Others can cost thousands of pounds for surprisingly small savings.
Before spending the money, it is worth understanding what you're actually buying.
What exactly is an EPC?
An EPC rates a property's energy efficiency from A, the most efficient, to G, the least efficient. It includes information about the property's estimated energy use and typical costs, along with recommendations for improving its efficiency.
In England and Wales, an EPC is normally required when a property is built, sold or rented. Importantly, an EPC remains valid for 10 years, so if you're thinking about selling, check whether you already have a valid certificate before paying for another one. Check your property's EPC on GOV.UK
How much does an EPC cost?
There isn't a fixed government price because assessors set their own charges.
However, a UK Government review published in March 2026 estimated the cost of a domestic EPC at roughly £70, based on industry information covering assessor fees, certificate lodgement and travel costs.
What is it actually measuring?
An EPC isn't simply a record of what the current owner spends on gas and electricity. The assessment looks at the characteristics of the building — including its construction, heating, insulation and glazing — to calculate its energy performance. That's an important distinction.
Two families could live in very similar houses and receive very different energy bills. One might heat every room throughout winter, while another uses very little heating.
The EPC gives buyers a standardised comparison, rather than predicting exactly what their particular household will spend.
But do buyers actually understand or care about it?
A buyer probably understands that B looks better than D. Whether they understand what the difference means financially is another matter. This is where some interesting research comes in.
A nationwide controlled field experiment investigated what happened when property advertisements showed buyers property-specific energy costs, rather than simply giving them technical information about energy efficiency. The researchers found that showing energy costs increased the premium buyers placed on energy-efficient properties. More efficient properties also sold faster, and displaying the energy-cost information itself further reduced time-to-sale.
In other words, telling someone what the energy efficiency might mean to their wallet appears to be more meaningful than simply giving them technical energy information (J. Carroll & E. Denny, R. Lyons, I. Petrov, Energy Economics, 2024)
For a seller, that raises an interesting point.
“What might this house cost me to run?”
could matter more to a buyer than whether its EPC score is 68 or 72.
It makes sense to improve EPC rating when...
Some EPC improvements aren't really about the certificate at all. They simply make the house better. Insulation is an obvious example. If a poorly insulated house is difficult to keep warm, improving the insulation can potentially mean:
lower energy use + lower bills + fewer cold areas + greater comfort + a better EPC
That is very different from spending money simply to move from one EPC letter to another. There is also evidence that buyers place a financial value on energy efficiency.
A particularly relevant UK study published in 2026 examined more than 170,000 second-hand property listings in Greater Manchester between 2017 and 2024.
The researchers found that buyers' willingness to pay for more energy-efficient homes increased following the 2022 energy crisis.
Interestingly, much of that change came from a greater price penalty for the least-efficient properties, rather than buyers simply paying ever-larger premiums for highly efficient ones. The findings also indicated that buyers were motivated at least partly by potential energy-cost savings (Y. Ou & N. Bailey, D. McArthur, Q. Zhao, Energy Research & Social Science, 2026)
There is also interesting evidence from London. A 2025 study examined repeat property sales in Greater London between 2013 and 2021, matching Land Registry transactions with EPC information.
The researchers found that the price premium associated with greater energy efficiency increased over the period studied. Their model estimated that by 2021, each additional EPC efficiency point was associated with approximately a 0.47% price premium in their London sample. The authors are careful to point out that their results are specific to London and should not automatically be applied to other parts of the country (J. Wei & R. Peiser, Land, 2025)
None of this means that changing your EPC from D to C automatically increases your property's value by a particular percentage. House prices depend on location, condition, size, presentation, supply, demand and dozens of other factors. But it does suggest that buyers aren't necessarily ignoring energy efficiency either.
When the numbers don't add up
This is where homeowners need to be careful. A better EPC doesn't automatically mean you've made a good investment.
Take windows. According to the Energy Saving Trust, a set of A-rated windows for a typical semi-detached house costs around £4,800. If that semi is currently entirely single glazed, replacing those windows with A-rated double glazing could save approximately £85 a year on energy bills in Great Britain.
Those figures give us a very simple calculation: £4,800 ÷ £85 = approximately 56 years.
On energy savings alone, that's difficult to justify for somebody planning to sell their home shortly. But that's not the whole story.
The Energy Saving Trust also points out that energy-efficient glazing can reduce draughts, cold spots and condensation and improve comfort. So perhaps the wrong question is: “Will these windows improve my EPC?” A better question might be: “Will these windows improve my home?”
If your existing windows are old, damaged, draughty or unattractive, replacing them could make perfect sense. If they're perfectly serviceable and you're replacing them mainly to gain a few EPC points before putting the house on the market, that's a very different calculation.
Then there are the expensive improvements
Solid-wall insulation gives us another good example. The Energy Saving Trust currently estimates that, for a typical three-bedroom semi-detached house in Great Britain:
Internal solid-wall insulation costs around £12,000.
External solid-wall insulation costs around £15,000.
That's serious money.
But solid-wall insulation can also reduce heat loss, lower heating bills, reduce draughts and make a home more comfortable. The Energy Saving Trust estimates that around 33% of the heat lost from an uninsulated home escapes through its walls.
For somebody intending to live in the property for another 15 or 20 years, those benefits could form part of a sensible long-term decision.
For somebody intending to put the house on the market next month?
Spending £12,000–£15,000 simply to improve the EPC deserves much more thought.
Will you get the money back when you sell?
This is probably the question most sellers really want answered.
Research showing that more efficient properties can achieve higher prices does not mean: Spend £10,000 → your house becomes worth £10,000 more.
The 2026 Greater Manchester study is particularly useful here because its findings suggest that buyers increasingly penalised the least-efficient homes following the energy crisis. The 2025 London study also found that energy efficiency was reflected in property values, but showed that this relationship changed considerably over time. And Carroll et. al's experiment suggests that buyers respond more strongly when efficiency is translated into understandable running costs.
Taken together, the research suggests something more nuanced than simply:
Higher EPC = higher house price. For a seller, removing an obvious weakness may sometimes be more worthwhile than chasing the highest possible rating.
Improve the home, not just the letter
An EPC is useful. It gives buyers a standardised way of comparing the energy efficiency of different homes and gives owners an indication of improvements they could consider.
The recent research also gives us reasonable evidence that energy efficiency can influence buyer behaviour, willingness to pay and selling time. However, an EPC shouldn't automatically become your renovation shopping list.
Before spending £5,000, £10,000 or £15,000 to improve EPC rating, I would ask four fairly simple questions:
Will this noticeably reduce the home's running costs?
Will it make the house noticeably more comfortable?
Will a buyer actually see or appreciate the improvement?
Am I likely to recover a reasonable proportion of what I spend?
That £4,800 window example demonstrates the problem perfectly.
Saving £85 a year produces a theoretical simple payback of around 56 years. But if those windows are cold, draughty and approaching the end of their useful life, the comfort, appearance and maintenance benefits might still make replacing them worthwhile.
Likewise, £12,000 or £15,000 of wall insulation might be a perfectly reasonable long-term investment for someone intending to stay in their home.
It doesn't necessarily follow that it's a sensible investment immediately before selling.
The EPC should therefore help you make decisions about your home. It shouldn't make those decisions for you.
My approach for somebody preparing to sell is fairly simple:
Improve the property where the improvement itself makes sense; don't spend thousands simply to chase a better EPC letter.
Sometimes the sensible improvement will also improve the EPC. Sometimes the money might be better spent repairing something buyers will immediately notice, decorating tired rooms or improving the presentation of the property. And sometimes the best decision is to spend nothing at all and let the next owner decide what improvements matter to them.
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