Cavity Wall Insulation Claims – Compensation for Problems with CWI

You may be eligible to claim compensation if cavity wall insulation has damaged your property or you have suffered adverse health effects as a result of the damp and mould caused by poorly fitted CWI. Typically, incorrectly installed cavity wall insulation causes water to seep into your home’s walls, causing damp patches, which typically manifest as black mould inside your home. However, much more serious problems can occur too such as subsidence and other structural problems.

In some cases, the damp and mould resulting from cavity wall insulation can cause health problems or exacerbate existing conditions, particularly respiratory conditions.

If you have cavity wall insulation installed in your property and you believe it is causing problems, then you may be able to claim compensation from the company that fitted it and have them cover the cost of removal. If the company is no longer in business, then you may still have a case, as their insurers will be liable for their shoddy workmanship.

Read on for further detailed information about CWI and the types of problems that it can cause for homeowners.

What is Cavity Wall Insulation?

Cavity wall insulation is the process of filling the cavity between the interior and exterior wall of a building with a filling that immobilises the movement of air. Although air possesses insulating qualities, still air is far more efficient at doing so than moving air. With cavity wall insulation, air remains the primary insulator but its movement is limited by the use of products such as rock wool, glass fibre or polystyrene balls. The objective is to prevent heat loss, thus reducing the cost of heating the home.

Cavity Wall Insulation Claims

In newly built homes, the insulation is fixed to the inner masonry block work (inside the cavity), still leaving a narrow cavity to intercept any rainwater that penetrates the outer face bricks. The insulation material is usually in the form of rigid foam boards, which are purposefully waterproofed or semi-rigid mineral wool. These fibres are then aligned vertically so that any penetrating rainwater should drain downwards in the cavity and not have the chance to penetrate across to the inner wall.

What is the Problem with Cavity Wall Insulation?

Most dampness problems do not show up in the first few weeks following installation; they become apparent after two or three winters, or sometimes even longer. Some customers will have dampness and condensation problems that they do not realise are caused by the CWI, and will therefore not have reported them to anyone, this is particularly true if the installation took place prior to them moving into the home. This problem has been exacerbated by the recent increase in usual weather events such as flooding.

Others have not noticed any physical symptoms, but neither have they seen the promised reductions in their fuel bills. If the walls and insulation hold moisture, any ensuing evaporation will actually cause a reduction in the thermal insulation qualities of the wall. This is a similar effect of wearing wet clothes, it doesn’t matter how many layers you wear, if they are wet, you will feel cold.

It is not true that only “unsuitable” walls can suffer from damp cavity insulation; no wall has ever been built well enough to withstand wind-driven rain.

Moreover, even in sheltered areas, retrofit cavity wall insulation is likely to cause problems. Thermal insulation requires the additional installation of a vapour barrier to be fitted to the inner leaf, this is not something that can be achieved by drilling a small hole in the face brick to stop moisture-bearing air from inside the dwelling finding its way through to the “cold” side and condensing out as liquid water. Retro-fit cavity wall insulation is a scientifically unsound idea.

Compensation for Problems with Cavity Wall Insulation

Prior to the use of cavity wall insulation being retrofitted, the only time that moisture penetration was a problem was when wall ties became dirty or were fitted with a slope, or debris built up in the cavity. In those cases penetrating rainwater could track across the cavity and show up as damp patches on internal decorative surfaces. However, the solution was easily fixed by the removal of offending wall ties in that area and debris being removed.

Wall ties are vital for the structural integrity of a building, as the name suggests, they tie the two adjacent walls together. As they are using made of iron or steel, the persistent presence of moisture will lead to corrosion. Failing wall ties can, in severe circumstances, lead to subsidence or buckling walls. Replacing wall ties wholesale is time-consuming and costly, the matter being made worse when CWI is in place.

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Who is Affected by Cavity Wall Insulation Problems?

Anyone with Retrofit Cavity Wall Insulation

If you have cavity wall insulation that was retrofitted, usually in houses built prior to the 1980’s you may well be affected. Even if there are no visible signs of damp or deterioration at present, this could occur at any time in the future.

There are certain areas of the country that are more badly affected than others.

What type of material was used to fill the cavity?

Most complaints arise from the use of blown mineral wool fibre. This product comprises of loose, wool-like, fibres that are blown into pre-drilled holes in the outer walls. Manufacturers and installers testify that the material is water resistant and it cannot allow water to track across to the inner wall; this is untrue as the fibres themselves can hold 243% moisture. Blown mineral wool fibre is not the only culprit, but certainly among the worst.

Having more external walls?

Evidently, the more external walls you have, the greater risk of exposure there will be, e.g. mid terraced houses will have half the external walls exposed than a detached property. Your risk is further increased if the exposed walls are facing the prevailing wind, which is typically from the south-west.

Poor workmanship?

Along with not actually having a suitable property for CWI, this is the second biggest problem. Recent analysis shows that anything up to 40% of houses with cavity wall insulation have the blown foam gaps in the insulation, and it is these gaps which cause condensation and black mould on the walls inside. This can be because, in a house which has been only partially insulated, the temperature still rises, and with it, the humidity – the amount of water vapour held in the air. Any remaining cold spots will, therefore, experience more condensation than before. Common areas for condensation and black mould growth are near ground level, between windows, and at ceiling level in upstairs bedrooms.

Gaps in insulation are caused by irregular or incomplete drilling patterns in the walls or by pre-existing blockages in the cavity itself. Just because you see an installer with a hose in the wall, how can you tell what is going in, how much and where it settles? You just have to take their word for it!

Installers are supposed to carry out thorough surveys of the cavity and only proceed if the all clear is given. This is rarely the case in practice, as often the problem does not become apparent until many years later. Choose your installer with care!

Why are so many people affected?

It doesn’t matter what the name of the company on the side of the van says, the cost of cavity wall insulation is nearly always funded by one of the major energy providers, and this is in direct response to pressures from the Government.

Energy suppliers have been put under pressure to hit government targets to insulate as many homes as possible, failure to achieve would result in fines. Among the notable initiatives are:

  • 1995 Kyoto protocol – a commitment to reduce greenhouse gases
  • 2008 Climate Change Act – to reduce CO2 emissions by 80% by 2050 from the 1990 baseline.
  • 2008 Carbon Emissions Reduction Target- A five-year obligation on energy firms to reduce CO2
  • 2008,10, 11 Energy Act
  • 2013 Ofgem Investigation into the big 6 energy company’s failure to hit their targets by 1%.
  • 2013 Green Deal – Energy efficiency scheme paid for by the reduction in future heating bills.
  • 2015 ECO2 – The energy company obligation to provide £1.3billion worth of energy saving funding every year, until 2017.

Of the estimated 19 million homes with cavity walls, 13.4million have been insulated which includes 3.4million since 2008.

For energy companies and insulation companies, this is an easy sell. Logic dictates that the more layers you put on the warmer you will be and the best bit is, it’s free! This is also great PR for the energy companies, even though the scheme is funded by a 7% levy on everyone’s energy bill.

Whilst this push from energy companies is led by government policy, it is neither controlled nor overseen by them. This is crucial, in the short term the government take all the plaudits for saving people money, in the long term they can deny responsibility when things go wrong

Another factor that the victims’ cases have in common is the role of the Cavity Insulation Guarantee Agency (CIGA), which issues 25-year guarantees. Salesmen often describe these as “Government guarantees”; they are not.

How Do I Know if I am Affected by Problems with Cavity Wall Insulation?

Common signs of poor insulation are;

  • Damp walls
  • Peeling wallpaper
  • Rotting wood work
  • Condensation on windows and other cold surfaces
  • Mould, mildew and fungus growth
  • Energy bills not being reduced or in some circumstances increasing
  • Subsidence and buckling walls

How Can I Claim for Cavity Wall Insulation Compensation?

Making a claim is easy, call us on or fill in our basic claim form. We will:

  • Assess your claim to see if you are eligible.
  • Call you to discuss your issues in greater depth, requesting further information such as photos and details of any communication you have had with the installer.
  • If not done so already, register your claim with the CIGA and the installer.
  • Arrange for a site visit to establish the scale of the issue.
  • Arrange for a loss adjuster to estimate repair costs.
  • Arrange for rectification work to be undertaken.
  • Sort compensation and handle any personal injury claim you may have as a result.

Who is responsible for my claim?

Responsibility for poor workmanship, in the first instance, rests with the people who sold you the service and or who installed it. In some circumstances, you may have forgotten the installer was, not owned the property when the installation took place, may not own the home or the installer is no longer trading. Carter Law can help you deal with all these eventualities.

Personal Injury resulting from Cavity Wall Insulation

Another unintended consequence of the cavity wall insulation is personal injury. Respiratory conditions can develop, or existing conditions can be worsened as a result. Common injuries sustained are

  • Fungal infections
  • Sickness
  • Vomiting
  • Shortness of breath
  • Bronchitis
  • Asthma
  • Sinusitis
  • Infections

Moulds produce allergens (substances that can cause an allergic reaction), irritants and sometimes, toxic substances. Inhaling or touching mould spores may cause an allergic reaction, such as sneezing, a runny nose, red eyes and skin rash. Moulds can also cause asthma attacks.

Obviously, if there is damp and mould in your property it may be hard to simply stay away from it. We can only recommend doing all you can to avoid prolonged exposure to the conditions, for example avoiding the rooms in your property affected by damp and mould to any extent possible. Furthermore, we recommend getting help as soon as possible in order to remove the damp and mould from your property.

Research has suggested that not only can damp and mould affect pre-existing asthma, it may be the cause of asthma in young children. Researchers for the European Respiratory Journal say that damp and mould can cause asthma as well as trigger attacks. The World Health Organisation has concluded that damp and mould to buildings can be associated with the development of asthma, aggravation existing asthma and eczema, as well as increasing various respiratory symptoms such as wheezing and coughing. Do these symptoms sound familiar?

Start Your Cavity Wall Insulation Compensation Claim

Do not hesiate to contact us if you believe that the cavity wall insulation in your property is causing problems. We can arrange for you to have a consultation with a housing law solicitor who has experience in handling claims relating to CWI and let you know what can be done to see that you’re awarded compensation.


To book a consultation with a housing law
solicitor, please call us on 0844 414 0667