Common Cavity Wall Insulation Problems You Might Face

Common problems with cavity wall insulation

If you’re looking for an affordable way to insulate your home, you’re probably considering cavity wall insulation. Though it’s one of the popular methods, it may result in various problems, such as cold spots and rain penetration.

So, you’re probably wondering: What are the common cavity wall insulation problems I might face? Is there a way to avoid these issues?

Look no further for the answers. In this article, we’ll help you understand what to expect from this kind of insulation and determine if installing cavity wall insulation is the right option for your home.

How Does Cavity Wall Insulation Work?

To better understand cavity wall insulation problems, you’ll first need to know how this method of insulation works.

The idea behind this insulation is to drill holes in the outside of your walls. Then, your installer will inject insulation materials into these holes to fill the wall cavity using special equipment. After that, the holes are sealed with cement.

These filling materials are typically mineral wool or polystyrene beads. Your installer might instead use polyurethane spray foam insulation as a retrofit cavity wall insulation option.

Although it seems simple, it’s not your typical DIY project. Ideally, you should find a registered installer to do this insulation for you.

The problem is that even with a professional doing all the work, you might still face various problems afterwards.

Cavity Wall Insulation Problems

Let’s check out some common wall cavity insulation problems you might face.

1. Moisture Penetration

The most annoying thing about cavity wall insulation is that it might allow some moisture to find its way into your house. In fact, this type of insulation can act as a bridge for moisture and carry it from the outside. That happens more often with loose-blown and mineral fibre fillings.

In addition, when the insulation becomes damp, it loses much of its insulating properties. Not only that, but it can also lead to peeling wallpaper and mould. Sadly, it may even turn into black mould, which might cause serious health issues for you and your family, eventually requiring the need to take action to remove cavity wall insulation.

2. Cracks Mean No Insulation

If your external walls were damaged or cracked for any reason, this simply means the end of your insulation.

The filling material will become damp in no time, losing its insulating properties. Unfortunately, cracks in the external brickwork are more common than you think. If the brickwork becomes damp and frozen, cracks might appear.

With these cracks, the insulation won’t be able to withstand severe weather. If it rains heavily, the rainwater may penetrate the wall, leaving damp patches on the interior wall.

Of course, you can always opt for expanded polystyrene beads, which can tolerate dampness. Still, if you live in an area where it rains a lot or have damaged exterior walls, it’ll be a risky situation.

3. Poor Installation Will Do More Harm Than Good

Cavity wall insulation isn’t forgiving at all. The slightest installation mistake will lead to annoying issues. All it takes is one unsealed hole in the exterior wall, and you’ll end up with useless insulation. Additionally, uneven and insufficient cavity wall insulation will lead to cold spots in your wall.

Cold spots, also known as bridges, are weak areas in insulation. These areas attract air moisture, leading to problems like black mould growth. Over time, these spots will be saturated with moisture. In turn, moisture will penetrate the wall and cause unpleasant odours in your house.

More importantly, you’ll be reaching for the thermostat more often, as the damp cavity wall insulation just won’t be working properly.

4. It May Cause Property Damage

Sadly, some types of cavity wall insulation can cause structural damage to your house. For example, in the case of bead cavity insulation, the materials are injected into the wall using an injection gun.

This injection gun pushes the over-bonded beads into the cavity. That can add a lot of pressure to the walls, which can cause cracks.

If you decide to opt for under-bonded beads, you could end up with another problem. Ants love creating nests between these beads, and they might end up inside your house.

How to Avoid Cavity Wall Insulation Problems

You can avoid a lot of the cavity wall insulation fails we’ve mentioned by following these steps:

1. Hire a Surveyor

You need to make sure your house is fit for cavity wall insulation. So, hiring a surveyor to assess the property is the right thing to do.

Typically, this assessment will analyse the property’s structure and ability to withstand this type of insulation material. The surveyor will also check the house’s exposure to rainfall and heavy wind.

2. Find a Certified Installer

After receiving the go-ahead from the surveyor, you’ll need to find a certified installer. Ideally, you want to find a reputable one who offers a guarantee for their work. We can help you there.

As an excellent insulation installer comparison tool, we can help find local insulation installers to you who have all been vetted as trustworthy professionals in the industry. And better yet, they’re ready to work with you today!

3. Keep an Eye Out for Alarming Signs

No matter how perfect the installation process was, you’ll need to check the walls every once in a while.

You want to keep an eye out for the following signs on the interior or exterior walls:

  • Damaged brickwork
  • Mould
  • Dampness
  • Condensation
  • Cracks
  • Falling wallpaper
  • Excessive heat loss

If you notice any of these signs, contact the installer as soon as possible. 

It’s worth mentioning that these problems might take a few years to come to light. So, make it a habit to check the cavity insulation regularly.

What to Do if You Face Cavity Wall Insulation Problems

If you spot any of the signs we’ve previously mentioned, the first thing to do is call the company that carried out the installation process. The installer will typically ask you a few questions and schedule a visit to your property. If the installation work was the cause of the issue, they’ll either fix the issue or remove the insulation and reinstall it.

All of the insulation installers we recommend are excellent at their job and trustworthy, so they ought to put things right if something goes wrong and they’re at fault.

In the worst-case scenario, your final option is to hire another company to carry out the fixes. It’ll be a costly process, but it’ll save your house from any further damage.

Is Cavity Wall Insulation Fit for Your Home?

Not every home can handle cavity wall insulation. If the walls are less than 40mm wide or more than 12 meters high, this method won’t be suitable.

Filling large walls with materials isn’t easy. You might end up with many cold spots or insufficient insulation which will impact on energy bills.

In addition, cavity wall insulation isn’t the best option for properties in areas that experience strong wind driven rain that batters external walls. Moreover, if your house has any kind of damage or cracks in outer walls, moisture will easily reach the insulation.

Frequently Asked Questions

1. Is cavity wall insulation worth it?

If a surveyor finds your house suitable for cavity wall insulation, go for it. Having this type of insulation is obviously preferable than not having any insulation at all.

Cavity wall insulation can help you save energy and cut down on your heating bills. It’s also a great way to reduce your carbon footprint and help save the planet!

2. How can CIGA help me?

CIGA – or the Cavity Insulation Guarantee Agency – is an independent agency offering cavity wall insulation guarantees. They will help you resolve issues caused by bad workmanship, poor materials, or overall inappropriate insulation.

In addition, you can report any company or installer that isn’t willing to help you with your insulation problems.

3. How do I know if the cavity wall insulation has failed?

You may notice cold or wet patches on an internal wall. You’ll also find that there’s high heat loss in your house. On any external wall, there may be signs of spalled or cracked brickwork. 

4. Does cavity wall insulation affect house ventilation?

Cavity wall insulation doesn’t directly affect your house’s ventilation. However, some installers might block or seal intentional ventilation during the insulation process.

5. How can I make sure the installer is trusted?

Work with Insulation Advisor! We carry out all of the comparison work on your behalf, and we only work with vetted, professional, and trusted insulation installers, meaning you can be confident that the businesses we recommend are installers you can trust.

You can also check the installer’s references and length of time in the business when we recommend them, and if you aren’t satisfied, walk away.

Cavity Wall Insulation Problems: Conclusion

Cavity wall insulation is a good way to improve energy efficiency and save money on your heating bills. Yet, it’s not a perfect insulation method, but many of the issues are often not to do with the insulation material itself, but rather faults with installation or the building itself.

Damaged or cracked exterior brickwork will allow moisture to seep into the insulation. In turn, the moisture can penetrate your cavity walls, not to mention that it ruins the insulation capabilities of the cavity wall filling.

On top of that, poor installation means the insulation will often do more harm than good. That’s why it’s crucial to hire a reputable installation company, like the ones we recommend at Insulation Advisor. It’s best to check your internal and external walls regularly for any signs of damage.

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