Updated 28th October 2022

Energy performance certificates (EPC) show how energy efficient, and environmentally friendly your home is - and how expensive your energy bills are likely to be. In this article, we outline some of the best energy efficiency measures you can take to improve your EPC rating.

How is your EPC rating calculated?

Your property's EPC rating calculation is determined by the amount of energy utilised per square meter. This encompasses energy consumption for heating, lighting, gas, and other factors. Additionally, the rating takes into account energy losses, which can occur due to inadequate insulation or thin windows.

Assessors work out your rating by first calculating the property's Standard Assessment Procedure (SAP) score, which follows the government's national calculation methodology. Subsequently, this score is utilised to determine the property's EPC rating.

Can I do my own EPC?

You’re not permitted to issue an EPC on your own, and while an estate may offer you the service, it’s advisable to arrange for the assessment to be conducted directly to get the most competitive EPC cost.

EPC rating bands explained

Every EPC comes with a chart of rating bands. This is is what each EPC rating band means:

What is a good EPC rating?

A good EPC rating is anything above a B. The best energy performance rating is ‘A’, which means a property has an efficiency score of between 92-100. The closer you can get to this score, the better!

However, most properties aren’t this energy efficient. The average rating for a property in the UK is ‘D’ - meaning they have an energy rating between 55-68.

Benefits of improving your EPC rating

Why should you improve your EPC rating? There are multiple benefits to having a better EPC rating.

• A higher energy performance rating shows buyers that they won’t have to pay huge amounts to run your home.
• This means that a higher EPC rating can improve the value of your home
• A better rating makes it a more attractive prospect for potential buyers and is a key part of the house selling process.
• As of 1st April 2018 it became a requirement for any property newly put on the private rental market to have an minimum epc rating, or energy performance rating of ‘E’. This minimum requirement was extended to all existing tenancies on 1st April 2020.

Making a few changes can significantly improve your score and help you save money.

How to improve your EPC rating

If you're keen to get the best EPC rating possible, the best way to improve your EPC rating is to make energy efficiency improvements and adjustments to your home's energy set up before the EPC inspector comes to call.

Below we list some of the top ways you can boost your property's EPC rating - and give our verdict on whether they are actually worth doing if you're planning on moving house soon.

Rule one - don't fix what's not broken

The changes you make will need to provide a genuine upgrade to your energy efficiency to improve your home's EPC score. Simply replacing already functional insulation or double glazing won’t make a difference, you may need to make some significant improvements.

Seven tips to improve your Energy Performance Certificate rating:

1. Improve the energy efficiency of your loft

• Cost: £100-£400
• Improves EPC rating by: 10-15 points
• Overall: Worth it

If your roof is not insulated, you can be losing a huge 25% of your home’s heat through it. In order to counter this - and make your home more energy efficient - it’s recommended that you have loft insulation at least 270mm thick.

Loft insulation comes in a variety of materials including: fibreglass, mineral wool, cellulose, or sheep's wool. These are commonly bought in rolls which are easy to install by laying out between and over the joists in your attic.

For a roll of around 8 metres squared, you can find insulation for as little as £20. This means you can insulate a small loft space yourself for less than £100.

If you prefer to hire a professional, installing insulation will take about a day, and usually costs about £400.

2. Add energy efficient wall insulation

• Cost: £500-£22,000
• Improves EPC rating by: 5-20 points
• Overall: Consider it

In the same way that your home loses a lot of heat through its roof, it’s also losing heat through its walls. The reason there is such a disparity in costs is because the type of walls you have can make a huge difference to the amount of work involved.

Cavity wall insulation is cheaper, as it involves filling in a gap that is already there. This makes it easier and less disruptive to install. This type of insulation can improve your EPC rating by 5-10 points.

Insulating solid walls is more difficult and considerably more expensive. But the improvement to your EPC rating that solid wall insulation will have is much greater. Heat passes through solid material at a faster speed than through a gap, so solid walls lose heat more quickly than with cavity walls.

If you have solid walls, insulating the external walls could be a good compromise. The insulation can be applied with minimal disruption to the household, and won’t reduce the floor area of your home.

You might also be able to apply for help with the costs of wall insulation. Search for grants available in your postcode on the Energy Saving Trust’s website.

3. Install double glazing or upgrade to triple glazing

• Cost: £2,000-£5,000
• Improves EPC rating by: 5-10 points
• Overall: Probably not worth it

Older windows can be responsible for up to 30% of heat loss in your house. But, because they only cover a small surface area of your walls, installing double glazing has a smaller - though not insignificant - impact on your EPC rating than installing wall insulation.

Going from single glazing to double glazing could add to your EPC rating by 5-10 points, but will cost about £250 to £400 per window. Triple glazed windows will deliver even more energy saving improvements.

Double or triple glazed windows are both great options that will improve your rating and the temperature in your house.

Simply replacing or upgrading any double glazed windows will not improve your EPC rating - you need to be upgrading from single glazing to double or triple glazing. Draught proofing windows and doors will also help.

4. Replace lighting with LED light bulbs

• Cost: £50-150
• Improves EPC rating by: 1-5 points
• Overall: Consider it

Replacing old halogen or incandescent light bulbs with energy efficient LED bulbs has a fairly small impact on your EPC rating - probably adding about 1 or 2 points. But if you’re on the border, this can make the key difference really quite cheaply. Energy efficient lighting is becoming more readily available and is coming down in price too.

5. Upgrade your old boiler

• Cost: Varies
• Improves EPC rating by: Up to 40 points
• Overall: Consider it

A new boiler can increase an EPC score by as much as 40 points for about £1,000 - £3,000.

So, although it is a substantial investment, if your old inefficient boiler is dragging down your score, replacing it with a newer more efficient boiler model may be an investment worth looking into to make your home more appealing to potential buyers - as well as driving down heating costs.

Smart metres will help you to monitor your energy usage too but won't directly impact your score. Having a modern efficient heating system will lower the running costs of your house and is a key pillar to your overall EPC rating.

6. Add a hot water cylinder jacket

• Cost: £20-£50

• Improves EPC rating by: 1-5 points

• Overall: Worth it

If you live in an old property, a cost effective way of targeting the failings of your old boiler is to insulate your hot water tank. Some suggest that a well insulated hot water tank can be just as efficient as a combi boiler. Although it won’t increase your rating by 40 points, you’ll still get a boost from reducing the heat lost from the water tank. (And it's a much, much cheaper upgrade.)

7. Install renewable energy

• Cost: £1,500+
• Improves EPC rating by: 5-20 points
• Overall: Probably not worth it

If you’ve done absolutely everything to improve your EPC score, then installing a renewable energy system is the best way to dramatically increase an EPC rating. Solar energy will make your home more efficient and more environmentally friendly too.

There are many grants being offered by local councils to help cover the cost of installing solar panels.

Larger solar panel electricity systems (also known as photovoltaics or PV) will have the largest impact on your EPC rating. Solar thermal systems will have a smaller effect as installing solar panels.

If you’re at the point that renewable energy is the only improvement you can make to your EPC score, it's likely you already have a very efficient household.

How to improve EPC rating from E to C

The level of effort required to improve an EPC rating from E to C can vary based on the property's specific characteristics, but generally, achieving higher EPC grades becomes increasingly challenging.

When comparing the difficulty, it's usually more demanding to move from a D to a B rating than from a B to an A. This is because achieving a B or an A rating typically requires more advanced technologies and substantial improvements in energy performance.

To improve your EPC rating, consider the unique characteristics of your property, including its construction, size, and existing energy systems. The results of your most recent EPC report should prove invaluable.

See if your EPC rating is up to date

Need an EPC? You can check here whether your home’s EPC is still valid, or get an instant quote for a new assessment here.