Don’t panic, most cavity wall insulation is perfectly safe, but it can depend on the materials used and the quality of the workmanship. Modern retrofit cavity wall insulation is perfectly fine to the homeowners, but if your household was retrofit decades ago, you may want to double-check to ensure that it’s entirely safe. Also, if the cavity walls were wrongly insulated, they again you may want to get it checked.
Urea formaldehyde foam insulation
In the 1970’s and 80s, there was a huge rush to insulate as many households as possible therefore formaldehyde was the widespread insulation used. It can be an effective insulant, however, when it’s in between the cavity walls, it begins to shrink which causes air gaps which increases cold bridging. A more problematic issue was noticed when this particular insulation began to decay and create chemical fumes. There’s evidence which connects these fumes to respiratory problems and health issues.
If you are worried that this particular insulation could be in between your cavity wall, it’s best to call out a professional who will be able to tell you what type of insulation it is and whether the air is dangerous. If so, it’s possible to remove it and replace it with a better material.
Blown fiberglass insulation
Fibreglass, again, was a commonly used insulator for cavity walls. It has no health effects when fully sealed within the cavity, but it only becomes a problem if it manages to escape between gaps. Fiberglass isn’t seen as a hazardous material but it is an irritant, so if there are gaps for it to escape, it can cause itchy eyes and skin.
Another problem with fiberglass is that if it was rushed when installed and water enters, it saturates the fiberglass causing it to provide absolutely no insulation and cause damp and mould, which can lead on to health issues. Again, you can hire a professional to help see whether you need new insulation or not; but bear in mind that you have to be extremely careful when removing it as you don’t want to cause irritation problems for your neighbours.
New cavity wall insulation
If you’re deciding to invest in cavity wall insulation, it’s worth ensuring that the insulation you choose is a material with proven insulating performance. The most common modern wall insulations are Expanded Polystyrene Beads (EPS) and Polyurethane foam as they cause no health implications and are waterproof, reducing damp and mould in the household.