During this project, we identified a serious cavity wall insulation failure caused by cross-contamination within the cavity. The original blown fibre insulation had been mixed with EPS carbon bead, creating an inconsistent and non-compliant installation that should never have happened. Rather than working as a proper insulation system, the mixed materials had compromised the cavity, leaving the property exposed to poor performance and increased risk of moisture-related issues.

This type of installation can lead to inconsistent density, poor bonding between materials and air gaps throughout the cavity, all of which significantly reduce thermal performance. In affected areas, the insulation was no longer performing as it should, increasing the likelihood of cold spots, condensation and damp problems within the property. In cases like this, patch repairs are not enough. The only proper solution is full extraction, complete cavity clearance and reinstallation carried out correctly.