The Complete Guide to Cavity Wall Insulation
Cavity walls are a common form of brickwork for residential and commercial properties. Typically, homes will have two standard types of wall, cavity walls or solid walls.
Solid walls are formed purely of brickwork and nothing else. There is no gap between two surfaces that is available to be insulated - external wall insulation must be sought out instead.
The second type of walls are cavity walls. These are usually found in homes that were built post 1920. A cavity wall is a type of wall that has a hollow centre. So, imagine two walls sandwiched together with a gap in the middle. More often than not, this gap is filled with some kind of insulation.
However, there are a significant number of homes across the United Kingdom that don't have cavity wall insulation. Unfortunately, this can lead to energy wastage, cold homes, and can even have a damaging effect on the houses' foundation too.
The first step to insulating your cavity walls is first identifying that you have one. Once you know if you have them, you can then assess the benefits of having your cavity walls insulated.
Indications That You Have Cavity Walls
Assessing whether you have cavity walls is actually quite an easy process. Simply follow these simple steps to get the answers that you’re looking for:
Find Out When Your House Was Built
If your home was built post-1920, then there is a good chance that your house has cavity walls. This is because cavity walls have been a common design for homes built post-World War 1.
Look For Patterns in Your Brickwork
Assess your brickwork for any recurring patterns. Depending on the pattern, you will be able to tell if it's a solid wall or a cavity wall. Typically, if walls have an even layout pattern, it is more likely to be a cavity wall.
Determine The Thickness of The Walls
Another simple technique to check for cavity walls is to check the thickness of your walls. Walls that are more than 260 mm (26 cm) thick are more than likely to be cavity walls. Solid walls tend to be thinner than this.
Measure The Brick Length
As with the pattern of the bricks, the brick length can also help you determine whether you have cavity walls. If all the bricks are a similar length, that’s a pretty good indication that it’s a cavity wall.
Check Your Loft or Attic
Additionally, you can check your loft too, as sometimes the external wall cavities have an insulation spill visible from there. Though this should be removed if so, it’s a strong indication that you have cavity walls.
If you are still unsure if you have a cavity wall, then you can ask a registered surveyor to drill a small hole in the wall in order to inspect it. This is known as “borescope inspection”.
Or, you can check with the building control department of your local authority, as they should hold records on your walls if they have been previously insulated.
Now we’ve been through how to check for cavity walls, let's look at the different cavity wall insulation types and their properties.
Cavity Wall Insulation Types
Identifying if you have a cavity wall or a solid wall is the first step in wall insulation. Now you need to decide what type of cavity wall insulation is best for you.
Different types will have various pros and cons, but with the same overriding objectives that benefit you and your home. The main types of cavity wall insulation are:
Let’s take a look at each type in more detail.
Blown-in Mineral Wool
This type of cavity wall insulation is fairly common and similar to loft blanket insulation, but instead of being provided in rolls, it is broken up and blown in.
Mineral wool insulation for cavities is typically inexpensive compared to other cavity wall insulation types. However, it doesn’t come without its drawbacks. The insulant will settle over time, which will cause air pockets at the top of the walls.
This will reduce your energy efficiency as more heat will escape through your external walls. Additionally, mineral wool must be kept dry, otherwise it will lose its insulant qualities.
EPS Beads Insulation
Insulating cavity walls with EPS beads is a long-lasting and innovative insulation solution. The beads are very efficient at trapping heat, and they cover all the gaps in the cavity, providing an extremely effective insulation.
Their ease of installation means that you do not need to use cavity boards in order to install EPS beads, either.
Previously, some drawbacks of EPS beads are the fact that loose granules can escape through airbricks, and, if in the future, you need any work done to your walls that involves drilling or cutting, you will need to be careful as EPS beads can spill out of the wall.
However, with new insulating technologies, a thin layer of adhesive can be added to the beads on installation. This will bond them together and prevent any bead leakage from your cavity walls.
We specialise in many forms of cavity wall insulation types, with EPS beading being one of them. So, if you’d like more information regarding this type of insulant, you can visit our dedicated page here.
Spray Foam Insulation
No list of insulation types would be complete without the mention of spray foam, also known as liquid cavity wall insulation. Spray foam insulation is an advanced insulant that offers the highest thermal protection. Though installation must be done by an expert, it is quickly and easily installed.
This type of cavity wall insulation creates an airtight seal that is almost impossible to break. It is this airtight seal that sets spray foam apart from other insulant types. This, alongside the many benefits that spray foam can bring to a property, mean it comes highly recommended by us, with little to no drawbacks.
What are the Benefits of Cavity Wall Insulation
We’ve briefly touched upon the fact that cavity wall insulation can bring about numerous benefits, but let’s look at them in some more detail.
When installing a high-quality cavity wall insulant such as EPS bead insulation, you can expect to reap the following benefits:
- Your house will be able to better regulate its own temperature. Staying warmer in the winter, and cooler in the summer, so you can expect a comfortable temperature all year round.
- As your home becomes more energy efficient, you can expect to see a reduction in your monthly energy bill too. Did you know that up to one-third of heat loss occurs through the walls? This means that you could save an estimate of £160 per year in heating bills.
- It doesn’t stop there. Installing cavity wall insulation can help improve your home's EPC rating. A higher EPC rating can increase the value of your property, and it demonstrates that you’re doing more to reduce your carbon footprint.
- EPS bead or spray foam cavity wall insulation typically lasts the lifetime of your property, so it’s extremely unlikely that it will ever need to be replaced in your lifetime. This makes it a cost-effective solution.
Plus, when you opt for Icynene spray foam insulation, you’ll also receive soundproofing benefits that will contribute to a quiet and peaceful living environment.
And if that wasn't enough, in light of its superior thermal capabilities, you're likely to see the best ROI when choosing cavity wall insulation. According to Energy Saving Trust, you could see a complete ROI on your cavity wall insulation investment within less than 5 years.
Let Us Take Care of Your Cavity Wall Insulation Needs
At Eco Spray Foam Systems, we are approved installers with the British Board of Agreement (BBA), the Cavity Insulation Guarantee Agency (CIGA) and the National Insulation Association (NIA).
We are also on the board of the NIA, reflecting our expertise in the insulation field. As a certified installer of cavity wall insulation, not only do we uphold a code of practice and are fully qualified, but we also provide a 25-year guarantee on spray foam insulation.
So contact us today, and let us take care of all your cavity wall insulation needs.