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Good cavity wall insulation can work wonders for your heating bills. By slowing the movement of heat through your walls, it helps your home stay warmer for longer. If your insulation isn’t installed right, though, you can suffer significant issues.
This guide explains when (and why) you might need to remove cavity wall insulation. It’ll go on to outline how to remove it, and who you can trust to do the job. Last but not least, we’ll calculate the cavity wall insulation removal cost you can expect to pay. Let’s get cracking before your walls do the same…
Why Would You Remove Cavity Wall Insulation?
The benefits of cavity wall insulation really came to the fore in the 1980s. During that decade, the UK government introduced new building regulations which stated insulation had to be installed in all new builds. At the same time, authorities and experts began to push cavity wall insulation for new homes, and also as a solution for older properties.
Companies of all shapes and sizes jumped on the cavity wall insulation bandwagon. Many of those firms were reputable and capable of installing the insulation properly. Sadly, some were not, leading to issues related to improperly installed insulation:
- Unsuitable Insulation Materials – Some unscrupulous firms used highly unsuitable insulation materials. Urea-formaldehyde is the prime example. It breaks down over time, causing two serious issues: it releases carcinogenic formaldehyde into the home and also falls down the cavity. Its use is therefore dangerous, and potentially leaves the top floor poorly insulated.
- Installation in Unsuitable Properties – Not all homes are suitable for cavity wall insulation. Timber frame homes should never have cavity wall insulation installed, and nor should insulation get injected into any wall that’s often subject to driving rain. Some dodgy installers preyed on the fact that homeowners often didn’t know this.
- Shoddy Insulation – Even where insulation may be beneficial, it can get installed incorrectly. There are a couple of ways some firms cut corners:
- When cavity wall insulation has been properly installed, the wall will have been drilled at regular intervals. Doing that ensures an even distribution of installation. If this isn’t done right, the wall will suffer from cold spots where the insulation doesn’t reach.
- The cavity wall insulation itself is often made up of beads. Proper insulation involves injecting both the beads and a uPVC glue to bind them. To cut corners, some installers only injected the beads. As a result, they fell to the bottom of the cavity, leaving the upper parts of the walls uninsulated.
- Damp Issues – As well as making the insulation inefficient, the above examples could cause problems with damp. Bad cavity wall insulation (or insulation where it shouldn’t be) can make a home more susceptible to damp. The insulation acts as a bridge between the external and internal wall surfaces, enabling moisture to travel more easily across to the internal wall. Which? has produced this handy guide to damp problems related to cavity wall insulation.
If any of the above circumstances apply to your property, you’ll want to get your cavity wall insulation removed. But what does this entail?
How Do You Remove Cavity Wall Insulation?
The process of removing cavity wall insulation is pretty straightforward, but you do need the right equipment and a high level of expertise and experience.
A selection of bricks gets removed at strategic intervals toward the bottom of the wall. Doing this provides access to the insulation itself. The gaps left by the removed bricks are for two purposes:
- Compressed air gets blown into the cavity through some of the gaps to loosen the insulation.
- An industrial vacuum gets inserted through other gaps to suck out that insulation.
A special instrument called a ‘borescope’ is also used throughout the process to inspect the cavity. Cavitech UK has created a video of the whole process that you can check out here.
Removing cavity wall insulation clearly isn’t a DIY project. If you need the job doing, you should seek out properly qualified professionals. A good thing to look out for when choosing a firm to trust is whether they’re OSCAR certified. This identifies companies and tradesmen that have proved themselves to be competent and reliable. Areas that OSCAR cover include roofing and decking, as well as cavity wall extraction.
Cavity Wall Insulation Removal Cost
The exact rate that cavity wall insulation firms ask for will depend on the kind of insulation that needs removing, as some varieties are more difficult to extract than others.
All companies charge for extraction by the square metre. The larger your property, and the more insulation that needs removing, the more you’ll have to pay. Most firms will charge somewhere between £20 and £30 per square metre. If you live in an area where everything is a bit pricier (i.e. London), you may have to pay a bit more. You’ll be lucky to find any extraction company that charges less. And given the costly issues that poor cavity wall insulation can cause, it’s often well worth the expense.
If you think damp or other issues in your home might be due to cavity wall insulation, you need to act.
Getting cavity wall insulation extracted isn’t something you can do yourself. You need to find a professional to get the job done right. And now that you know what to expect when it comes to cavity wall insulation removal costs, you’re ready to hunt out the ideal tradesman.
If you’ve got any other questions, leave a comment below to get a conversation started or share this guide on social media.