How to Improve Your EPC Rating

What Is an EPC?

An Energy Performance Certificate (EPC) rates how energy efficient your home is on a scale from A (most efficient) to G (least efficient). It also provides an estimate of your energy costs and recommends improvements that could boost your rating. EPCs are required whenever a property is built, sold, or rented, and they are valid for ten years. Your EPC rating is not just a piece of paperwork — it directly affects your eligibility for government grants, your energy bills, and your property value.

Understanding the Ratings

EPC ratings are scored from 1 to 100, with higher numbers indicating better energy efficiency. Band A properties (92-100) are the most efficient, while band G (1-20) are the least. The average UK home currently sits at band D, with a score around 60. Most government grant schemes — including ECO4, GBIS, and HUG2 — target properties rated D, E, F, or G, so having a lower rating can actually work in your favour when it comes to accessing free funding for improvements.

Your EPC includes a breakdown of how your home performs across key areas: walls, roof, floor, windows, heating, hot water, and lighting. Each area is rated individually, so you can see exactly where your home loses the most energy and prioritise improvements accordingly.

Quick Wins: Low-Cost Improvements

Some of the most effective EPC improvements are surprisingly simple and affordable. Draught-proofing windows, doors, and letterboxes can make an immediate difference to both comfort and your energy rating. Replacing old halogen or incandescent light bulbs with LED alternatives throughout your home is another quick win that EPC assessors will note. Installing a hot water cylinder jacket if your tank is uninsulated, and adding reflective radiator panels behind radiators on external walls, are low-cost measures that can nudge your score upward.

Upgrading your heating controls can also have a noticeable impact. Adding a room thermostat, thermostatic radiator valves (TRVs), and a programmer or smart thermostat demonstrates better control over your heating system, which is positively reflected in the EPC methodology. These upgrades typically cost a few hundred pounds but can improve your rating by several points.

Major Improvements: Insulation and Heating

The biggest gains in EPC rating come from insulation and heating system upgrades. Loft insulation to the recommended depth of 270mm is one of the most cost-effective improvements, typically raising a rating by 5-10 points. Cavity wall insulation can deliver even larger gains, particularly in older properties where uninsulated cavity walls allow huge amounts of heat to escape. External or internal wall insulation is more disruptive and expensive but provides excellent results for solid-walled properties.

Replacing an old, inefficient boiler with a modern condensing model can improve your EPC by 10-15 points. Upgrading to a heat pump takes this further still, as the EPC methodology rewards renewable heating technologies with higher scores. Double or triple glazing, while expensive, can also contribute significantly — particularly if you currently have single-glazed windows.

How Government Grants Can Help

The good news is that many of the most impactful EPC improvements can be funded through government grants at no cost to you. The ECO4 scheme can fund loft insulation, wall insulation, heating upgrades, and even solar panels for eligible households. The Great British Insulation Scheme (GBIS) specifically targets insulation measures for homes in Council Tax bands A-D with low EPC ratings. The Boiler Upgrade Scheme provides up to £7,500 towards a heat pump, which delivers one of the biggest EPC improvements of any single measure.

By combining measures from different schemes, it is possible to transform a property from band E or F to band C or even B — all at little or no cost. This not only cuts your energy bills but also removes future barriers if minimum EPC requirements for rental properties are tightened, as the government has signalled.

Impact on Property Value

Research consistently shows that homes with higher EPC ratings sell for more and sell faster. A study by the Department of Energy and Climate Change found that improving from band G to band E can add around 6% to a property's value. Moving from band D to band B can add even more. In a competitive housing market, buyers are increasingly factoring in energy costs when making offers, and a good EPC rating provides reassurance that bills will be manageable.

For landlords, the stakes are even higher. Current regulations require rental properties to have a minimum EPC rating of E, and the government has proposed raising this to C for new tenancies. Landlords who invest in energy improvements now — many of which can be grant-funded — will be ahead of the curve and avoid potential penalties or the inability to let their properties.

Steps to Get Started

• Obtain your current EPC — if it is more than a few years old, consider getting a new assessment to reflect any improvements you have already made
• Review the recommendations section of your EPC, which lists suggested improvements and their estimated impact
• Start with quick wins like LED lighting, draught-proofing, and heating controls
• Check your eligibility for government grants to fund insulation and heating upgrades at no cost
• Consider whether a heat pump or solar panels could further boost your rating and reduce long-term energy costs
• After improvements are completed, commission a new EPC to confirm your updated rating