Is Cavity Wall Insulation Suitable for My Home?

Considering cavity wall insulation but you’re not sure if it’s worth it? No need to worry, we got you covered. Did you know that about a third of all the heat lost in an uninsulated home escapes through the walls, according to the Energy Saving Trust.

Cavity wall insulation fills all the gaps that can be found between external walls in homes, keeping the warmth in, to save both energy and money. But that's not all, insulating your cavities can also help reduce condensation inside the house if this is a problem stemming from your external walls.

Your property will usually be suitable if it meets the criteria:

 The masonry or brickwork of your property is in good condition

 Your cavity is at least 50mm wide

 External walls are unfilled cavity walls

 It is more than 20 years old

energy efficient home

evergreen power uk accreditations

The Big Question: Do I Have Cavity Walls?

It's easier than you think, there are 3 simple steps to check yourself which will tell you if your home has a cavity wall. If in doubt, we can carry out a free professional survey.

Check 1: How old is your home?

Cavity walls didn't really start to be used in general building construction until the early 1930s, which is why the age of your home is a vital first step. If you have an old house without cavity walls then check out what to do here.

When was your house built?

Before 1932 - Unlikely to have a cavity wall

1932 to 1982 - Highly likely

After 1982 - Almost Certain

External wall insulationCheck 2: What pattern are the bricks on your external walls?

There are 3 common types of brick walls.


Measure thickness of external wallsCheck 3: Measure the thickness of your external walls

Cavity walls tend to be thicker than solid walls because they have an air gap between the external and internal wall. It's easy to measure, simply open your front or back door and measure from the outside face of the external wall, through the door to the inside face of the internal wall. Please note: Layers of internal plaster or external render will affect the thickness so a rough figure will do.

Outside Wall Thickness:

Less than 30cm (11.5 inches) - No Cavity Wall

More than 30cm (11.5 inches) - Yes. You got a Cavity Wall


Introducing an Unheard of Alternative to Cavity Wall Insulation

When you think cavity wall insulation, you instantly think of injected, blown fibre or polystyrene balls... News Flash: this insulation method is now a thing of the past and over time causes more problems than it solves. Did you know that there are now companies removing cavity wall insulation?

cavity wall home insulation treated

Hence why we have introduced an external wall coating called ProPERLA masonry creme based on the latest nanotechnology. First off, this revolutionary product prevents thermodynamic heat loss and consequently keeps your home warmer. But that's not all, it also creates an invisible insulation barrier that can reduce water absorption by more than 95%. WATCH ProPERLA in action here.

Keep the Weather Out & the Warmth In

Look at it this way, keeping walls dry reduces heat loss and contributes to lower energy consumption and lower energy bills. A damp content of 5% in a plain brick wall can lower the insulation by up to 50% especially where cavity wall insulation has been installed. Find out more here.

Properla masonry creme application process

external wall properla insulationSuper Hydrophobic - You will recognise the excellent water repellent property by its beading behaviour. It will make the masonry dry and extremely resistant to biological hazards, mould, mildew and others. A dry masonry will improve the thermal resistance, prevent frost damage and reduce the growth of microbial spores.

external wall breathable insulation properlaBreathability - The masonry is able to breathe and permeable to water vapour and it lets air and moisture pass through from one side to the other. A breathing masonry will improve the thermal conductivity and insulation properties. Just a 5% content in cavity wall insulation can lower the thermal resistance by up to 50%.

external wall self cleaning properla insulation Self Cleaning Efficiency - The superior technology mimics the ‘lotus-leaf’, repelling dirt and water to give a superhydrophobic effect, making walls self-cleaning. Dirt particles are unable to obtain a hold on ProPERLA treated surfaces and will simply flow off with rainfall.

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Frequently Asked Questions

What is cavity wall insulation?

Cavity wall insulation fills the gaps between external walls. Every part of the wall must be filled with insulation correctly, so its important the right installer does it for you.

How is the insulation installed?

To insulate your cavity walls, the installer drills small holes at intervals in the outside wall of your home. The installer then blows insulation into the cavity using special equipment. Once all the insulation is installed, the installers fill all the holes in the brickwork.

Can I do the insulation myself?

Filling cavity walls is not a job you can do by yourself, you will need to hire a professional contractor.

What wall type do I have?

Houses in the UK mostly have either solid walls or cavity walls: A cavity wall is made up of two walls with a gap in between, known as the cavity; the outer wall is usually made of brick and the inner layer of brick or concrete block. Whereas a solid wall has no cavity, each wall is a single solid wall, usually made of brick or stone.

Still have a question? Contact our team today