cavity wall insulation removal cost

Cavity Wall Insulation Removal Cost in 2024 (UK Price Guide)

Good cavity wall insulation can work wonders for your heating bills. Slowing the movement of heat through your walls helps your home stay warmer for longer. If your insulation isn’t installed correctly, you can suffer significant issues.

This guide explains when (and why) you need to remove cavity wall insulation. I outline the process of removing it and hiring a trusted professional. Lastly, we’ll calculate the cavity wall insulation removal cost you can expect to pay. Let’s get cracking before your walls do the same.


In a Hurry? Find top-rated builders in your area by clicking the button below:


Why Would You Remove Cavity Wall Insulation?

The benefits of cavity wall insulation 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 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 use highly unsuitable insulation materials. Urea-formaldehyde is a prime example. It breaks down over time, causing serious issues. I.e. it releases carcinogenic formaldehyde into the home and falls down the cavity. Its use is, therefore, dangerous and potentially leaves the top floor poorly insulated.
  • Installation in Unsuitable Properties – Not all homes suit cavity wall insulation. Timber frame homes should never install cavity wall insulation, nor should insulation be injected into any wall subjected to driving rain. Some dodgy installers preyed on the fact that homeowners often didn’t know this.
  • Shoddy Insulation – Even where insulation is beneficial, it can be installed incorrectly. There are a couple of ways some firms cut corners:
    1. Properly installed cavity wall insulation is drilled and filled evenly across the whole wall. If done incorrectly, the wall suffers from cold spots where the insulation doesn’t reach.
    2. Cavity wall insulation is often made up of beads. Correct installation involves injecting the beads and uPVC glue to bind them. To cut corners, some installers only inject the beads. As a result, they fall 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 bridges the external and internal wall surfaces, enabling moisture to travel 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 need the right equipment and a high level of expertise and experience.

A selection of bricks gets strategically removed 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:

  1. Compressed air gets blown into the cavity through gaps to loosen the insulation.
  2. 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 isn’t a DIY project. If you need the job done, you should seek out properly qualified professionals. An important thing to consider when choosing a reputable firm is whether they’re OSCAR certified. This identifies companies and tradesmen who have proved competent and reliable. OSCAR covers areas including roofing, decking, and cavity wall extraction.      


Cavity Wall Insulation Removal Cost in 2024

The exact rate that cavity wall insulation firms ask for will depend on the insulation that needs removing, as some varieties are more difficult to extract than others.

All companies charge for extraction by square metre. The larger your property and the more insulation that needs removing, the more you’ll have to pay. Most firms charge 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.  


Don’t fancy doing this job yourself? Find top-rated builders in your area by clicking the button below:


Final Thoughts

You must act if you think damp or other issues in your home might be due to cavity wall insulation. 

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 regarding cavity wall insulation removal costs, you’re ready to hunt out the ideal tradesman.