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What is an EPC?

What does your EPC say about your home?

My name is Penny, and during the last year of working for Cobalt Carbon Free, I have learned a lot. I had no experience in the construction industry before working here, and it took me by surprise how much of it has helped me in my home life, not just at work! Hopefully, you will also find use in what I have shared below.

So, EPC’s! One of the first things we do when we receive a new enquiry, is to look online and see if your property has an EPC. Why do we do this? Because looking at your EPC helps us to analyse what is going on in your home before we have even stepped foot in it, which in turn helps us to advise you on the options for making your home more energy efficient.

But what actually is an EPC?

EPC stands for Energy Performance Certificate and is an assessment of how energy efficient your property is, by assessing its energy usage and the energy saving measures that are in place e.g. if any insulation is present and what sort of heating system you have. All of these individual ratings are combined to give an overall score for the property, which is then given a letter rating between A and G, as seen below. A being the most energy efficient and G being the least.

It provides a lot of useful information, including details of each feature on your property that affects energy use, such as whether you have cavity or solid walls, the amount of loft and underfloor insulation that you have, and what kind of heating and windows you have installed, even down to the types of lightbulbs you have in your light fittings, as these all effect how much energy your home uses.

The EPC we are looking at has a rating of E, which is very poor for a house by today’s standards. It belongs to an old Victorian terraced property that has solid walls, no Underfloor insulation, and a very old heating system.

You can see in the image to the right, that these are all rated as poor or very poor and have a big effect on the rating. In short, this means that the property would be hard to heat, and the heat retention would be very bad, so if you wanted the house to be kept at a comfortable temperature, you would need to use a lot of energy.

You will see that on the image that it explains the meaning of when a feature is described as ‘assumed’. This is often used when an assessor has been unable to definitively assess a particular feature, so an assumption is made based on the age of the property.

There are a lot of things you can do to improve the rating and energy efficiency of a property, and the EPC lists them for you further down the page.

Your EPC also gives you an idea of your estimated yearly energy bills. This EPC is a few years old, so is a bit out of date as energy prices have risen significantly since this was produced, but it still gives you a good idea of how much energy your home will use over the year. It also gives you an estimation of how much you could save by installing some energy efficiency measures, such as External Wall Insulation or improved Loft insulation, and gives a good insight into how valuable improving the insulation of your home could be.

The next bit of information as you go further down the document, is suggestions of changes you could make to the property, with a suggested cost, the amount a year it could save you on your energy bill, and how much it would improve your EPC rating, as you can see on the image to the left.

For this particular property, the measure that would make the biggest impact is Internal or External Wall Insulation. When these are installed together, we call it Hybrid Wall Insulation.

This is the most recommended improvement because the property is Solid Wall, rather than cavity, so the biggest amount of heat loss by far is through the external walls. Having Solid Wall Insulation installed would be the best step to take first, as it would add 7 points to this EPC, and would save you the most on your energy bills for the year. We have recently gathered some feedback from customers who have had EWI completed on their property for at least a year, and they have all saved at least 30% on their energy bills! The biggest saving was a customer that had EWI and underfloor insulation installed, and their energy bills have been cut by a whopping 49%!

Suggestions vary greatly from property to property, depending on what you already have installed on your home, and the construction of the walls and flooring. It gives you a good guide to start from, but the best way is to have an assessment done by a specialist company such as ourselves, we can spot things that could be missed by the EPC assessor, especially when a measure is classed as ‘assumed’. If you have cavity wall for example, we can insert a specialist camera into the cavity, to assess what the condition of the filling is and what percentage of the walls are still sufficiently filled.

But what is the point of an EPC?

In all honesty, before I started working for Cobalt Carbon Free, I had no idea what an EPC really meant! I had heard the term thrown around, especially when moving house and being given the documents for the property when moving in, but I had never given them much of a look or thought, as I didn’t know the impact it had.

Now having learnt more about energy efficiency, and what impact a poor EPC can have on the comfort and cost of running a home, I pay attention to them.

As well as helping you to potentially improve the efficiency of your current home, an EPC is especially important to look at if you are looking to move to a different property, regardless of whether you are buying or privately renting. If you are buying the property, it will give you insight into what work you may need to consider having done in the future to make the property more sustainable and energy efficient, and even if renting it gives you an idea of how expensive it will be to heat the house and how well it will hold the heat. It is also important when selling, as other buyers will look at it and if it is particularly bad, it could put people off.

Does my homes rating really make a difference?

I myself have lived in two properties with greatly differing EPC ratings, one with a rating of E and one rated C. The house rated E was always cold, difficult to heat and the heat retention was awful, as it had so little insulation. We could rarely afford to have the house at a comfortable temperature, as the cost was so high. The house rated C was a lot easier to heat, due to its updated heating system, and because of it having loft insulation and cavity wall insulation, held the heat for a lot longer, meaning I could have the heating on for a shorter period of time, saving energy and making it more affordable for me to comfortably heat. The money I then saved form my energy bills, allowed me to make other improvements to my home.

Find out if your home has an EPC here, then if you would like to know more give us a ring or fill out our contact form and we will be happy to apply our experience to help you create a more energy efficient home fit for the future.

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