When you had your cavity wall insulation installed, you probably were excited about all the benefits. After all, the Energy Saving Trust suggests that you could save as much as £275 a year on your energy bills from having this type of work carried out. But has it become a nightmare for you because of damp issues? If so, you are probably wondering what on earth you can do to correct the problem. Millions of people are discovering that the insulation they had installed (often free of charge under government schemes), in the hope of reducing energy costs, are actually now having the exact opposite effect, causing damp and mould problems.
How can wall cavity insulation cause damp?
First of all, it’s worth noting that not all damp problems are caused by faulty cavity wall insulation, and equally not all cavity wall problems will end up causing you issues with damp. Despite the fact that most people’s cavity wall insulation will continue to provide them with energy and efficiency savings over it’s lifetime, unfortunately some installations can result in serious damp problems.
Cavity wall insulation is designed to do one thing; to insulate the cavity in your wall. Insulation material is pumped into the cavity between the outer brick of your house, and the inner brickwork. The type of material used for the insulation does vary, but essentially it serves the same purpose – which is to increase the insulation of your cavity – therefore reducing the transfer of energy between the inside and outside of your home. For the insulation to function effectively, the cavity must remain dry. If the material used to insulate your wall does get wet, then this can transfer moisture to your inner walls, causing mould and damp problems.
If you have cavity wall insulation but are not currently experiencing damp problems, then it is wise to try to protect your walls against the ingress of water, which could result in damp problems. One of the most common reasons for cavity wall insulation to fail, is simply due to outer brickwork being in poor condition. If you live in a particularly wet or windy area (for example on an exposed coastline), you should consider that you may need to ensure that your wall is regularly maintained, repairing any lose grouting or badly eroded bricks before they cause bigger problems.
What can I do?
If your home is affected by damp following the installation of wall cavity insulation then the only solution is to have the wet insulation removed or extracted. This is a job that needs to be carried out by a qualified and experienced contractor and can be costly. Your contractor will open the holes in your outer wall that were in place for the installation and use a vacuum pump to suck out the insulation. They may also need to use high pressure hoses to dislodge it. If you have solid wall insulation the process will be more costly as parts of the wall may need to be removed.
Your contractor will be able to tell you if you should consider having the insulation re-installed. If your walls are correctly repaired, then this might be suitable but you should be fully convinced that your home is not at risk of further damp issues. The Telegraph have recently reported on an increased volume of cases of wall insulation going bad, and we echo their concerns that there may be many more houses that will require their insulation to be removed.
How will I pay for the removal?
This is a tricky one and no clear answers seem to be available at the moment. You may feel that your guarantee will mean that the company that did the installation is liable, this isn’t always the case – but it should certainly be your first port of call. If you went through your energy supplier, you could also contact them for advice.
There is another organisation that may be able to help, if you aren’t getting anywhere with your installer – that’s the Cavity Installation Guarantee Agency (CIGA). If your Cavity Wall Insulation was guaranteed by CIGA (if it is then you would have been given a certificate by your installer at the time of installation, or from the previous owner if you have purchased the house with insulation in place), then their website states that they may be able to cover the cost of removal if the insulation has failed within the 25 year guarantee period. CIGA state that your installer must be notified of any problems as soon as possible, and that CIGA may then be contacted if the matter is not resolved satisfactorily within 2 months.
If neither your installer or CIGA can help, then your last report may be to contact your home insurer, as this type of damage may be covered under your buildings insurance. This is especially the case if the insulation has been affected by flooding or unusually poor weather.
If you’re concerned that your cavity wall insulation may be causing damp, then we would recommend you speak to a qualified professional who can survey your property and tell you whether removal is the solution to your problems. You can find more information on how to find a supplier in your area on our dedicated cavity wall insulation removal page.