Why should you Insulate your Cavity Wall?

If your home experiences cold winters, high energy bills and is subject to loud noises, then you could be looking at a simple and easy fix, cavity wall insulation. Insulating cavity walls is one of the most effective ways to curb excessive noise and provide that much needed warmth throughout the winter months. External walls of a home experience one of the highest (if not the highest) percentage of heat loss, averaging up to 35% of heat loss. Therefore, by installing a sufficient insulant to reduce this percentage, your home will be better off for it. Whether you live in London, Manchester or anywhere else across England, you should make sure you prepare for those harsh winter months with a sustainable and effective home insulation solution.

What is a Cavity Wall?

You may not have come across this term before, you think of a home and just know it has walls, interior and exterior. However, most homes post-1920 have been fitted with a different type of external wall, a cavity wall. A cavity wall is simply a wall in your property that has a gap in between another wall. If your external walls are separated by spacing in between and another wall, then you have got yourself a cavity wall. Traditional singular external walls have become outdated and inefficient due to their inability to sufficiently insulate. If you are still unsure if your home has a cavity wall or not, then check out these tips below that can help you identify your home’s external walls.

How do you know if you have a Cavity Wall?

There are a multitude of ways that can help you distinguish if your home has a cavity wall. Below is a list of quick tips that can instantly help you identify a cavity wall.

  • Brick Pattern,
  • Property Length,
  • Thickness,
  • Visual,
  • Brick Length,
  • Holes,
  • House Age

Brick Pattern

If the brick layout pattern is even, then your wall is likely to be a cavity wall.

Property Length

If all the properties of your external wall are the same length.


Cavity walls use brickwork that is more than 260mm thick.


Sometimes you will be able to look down the cavity directly from your attic.

Brick Length

Check the lengths of your bricks, if they are all similar, then this could be an indicator of a cavity wall.


Does your external wall have a series of holes in between the bricks? This could insinuate where insulation has been sprayed in and shows that you have a cavity wall.

House Age

Most homes that were constructed after the 1920s commonly use cavity walls for their external walls.

What are the benefits of Cavity Wall Insulation?

Once you have understood what a cavity wall is, identified that you do indeed have a cavity wall, you can then relish in the benefits of cavity wall insulation. So, what are the benefits of have your cavity walls insulated?


First and foremost, the thermal enhancements you will gain with cavity wall insulation will be sure to keep your house warmer in those cold winter months. As previously mentioned, you home can lose up to 35% of heat through the walls, therefore, by using a quality insulant to add resistance to this heat loss, you will conserve heat and keep it in your home, providing a better quality of life. Some insulation products are better than others at conserving this heat, see below for our recommend products for insulation cavity walls.


An important factor that everyone should consider is the environmental impact. By adding insulation to your cavity walls you will reduce your reliance on heating and cooling (yes, cavity wall insulation is also more efficient in the summer months), therefore, you will consume less energy, reducing your carbon footprint. Additionally, one of the main products for cavity wall insulation, spray foam, is an environmentally friendly insulant, using no toxins, letting off no carbon emissions and is even composed of recycled materials.

Money Saving

As we have deduced, you will reduce your energy consumption with cavity wall insulation, therefore, your energy bills will be significantly lower every month. It is possible to save up to 30% on your energy bills every month when your cavity walls have been insulated. Thus, cavity wall insulation is not just a paid service but an investment, saving you money on your energy bills every month, that you will see a return on.

Noise Reduction

There are many insulants on the market today that show properties beyond thermal capabilities, such as spray foam insulation, more specifically, open cell foam insulation, this product can provide a soundproof area for your rooms, in addition to the thermal benefits. Therefore, if you home is subject to noisy neighbours or loud street noises, open cell spray foam may be just what you are looking for.


Cavity wall insulation, in its more modern form, can be extremely easy to install and uses non-invasive techniques. When you invest in a spray foam insulant, it is a simple matter of drilling holes in specific areas of your wall to inject the foam insulant and filling the wall as such. Cavity wall insulation is, therefore, an easy-to-install process, giving you many benefits with minimal disruptions.

Added Value

Having your external walls insulated can add value to your property. Any home that has cavity wall insulation, especially if it uses a good insulant, it will be able to save money monthly and by enhancing the quality of life due to its thermal and soundproofing capabilities, your home will be a better place to live, thus, increasing the value of your property.

Where to get the best cavity wall insulation installed?

When you sign up with Eco Spray Foam Systems, we provide a free survey of your home, detailing how cavity wall insulation can benefit you and provide a transparent and friendly service. We have accumulated decades of experience in the insulation field and were one of the first providers of spray foam insulation in England. Our teams have insulated homes across England and have by reviewed by many customers, you can see our Checkatrade rating here. If you wish to work with us, contact us at www.sprayfoam.co.uk/contact.html or call us directly on 0203 411 5188.

You can ask us anything, if you just want to find out more information or want you free cavity wall survey, then we would be happy to assist. We are your insulation specialists.