What Are the Different Types of Cavity Wall Insulation?
Cavity wall insulation (CWI) is a great way to improve the energy efficiency of your home and save on your heating bills – as long as it’s installed correctly. Over the past 20 years, millions of homes have had their cavity walls incorrectly insulated, sometimes costing them tens of thousands in repair bills.
This is why it’s so important homeowners a clued up about cavity wall insulation and their rights if they’ve been the victim of a dodgy installation. In this article, we’re going to explain the different types of cavity wall insulation that you might have fitted in your home and the potential problems that could arise.
Mineral fibre or wool
The most common method of fitting an existing property with cavity wall insulation is to insert mineral fibre or wool. Both materials can be used anywhere in Britain and they’re covered by British Board of Agreement (BBA) certificates and installations with certified professionals are guaranteed for 25 years.
The materials are mechanically injected into your walls through holes drilled through the outer layer of bricks. It’s important either material is kept absolutely dry prior to and during installation, otherwise it could lose its ability to insulate and air pockets may develop over time, which is how you end up with trapped moisture and damp.
Polystyrene is a great insulator and relatively easy to install in a property after completion. Beads are generally combined with a binding agent, which helps them stick together and form a solid layer of insulation, and then injected with a specialised injection gun. Beads are injected at specified sequences to ensure your cavity is completely filled.
This is the crucial factor: that your walls are tightly sealed to prevent any air pockets developing, where water can become trapped and develop and cause damp.
It’s also important that no loose granules are able to escape through airbricks or other holes in your wall. The risk of this can increase if you have any work done to your home – particular if it involves drilling into your walls or anything that causes heavy vibrations.
Polyurethane foam offers the best quality of insulation but it’s also the trickiest to install. You always need to make sure cavity wall insulation is inserted by qualified professionals but it’s worth checking that your installer has experience with this method before beginning.
Once again, holes are drilled into the external layer of bricks and the material is injected using an injection gun. The foam injected is expandable, which should mean gaps are less likely to be left, as long as it’s correctly installed.
However, polyurethane foams are generally sold as being guaranteed for the life of your property but numerous foams have been found to degrade over time.
Each type of cavity wall insulation has their pros and cons but the important thing is they’re installed correctly. If you suspect your home has been damaged due to poorly installed CWI, get in touch with our team today.