Homeowners choosing to have cavity wall insulation installed in their homes often choose to do so to cut energy bills and believe they can rely on installers to provide trustworthy advice and follow best practices. However, a report following an investigation into Welsh homes suggests this isn’t always the case and calls for a nationwide survey should be a cause for concern for both those that are considering the measure and those that have already had it installed.
The latest survey was conducted for Constructing Excellence in Wales (CWE) and follows hundreds of homes in the country needing to have cavity wall insulation removed after installations caused damp and condensation. Other unintended consequences included cracking in the walls of properties. The removal of the insulation not only presents an additional cost to homeowners but they also face the need to repair the damage faulty installations have caused. The report for CWE was conducted to investigate the extent of failed installations across Wales.
It’s thought that around half of all cavity wall dwellings in Wales had had cavity wall insulation installed by 2008, amounting to some 900,000 homes, although the figure is likely to have significantly risen since then. The report noted, “There is evidence that cavity wall insulation or external wall insulation, has been installed in unsuitable properties, or without due regard for best practices.”
More worrying is that all the cavity wall insulation failures occurred within the guarantee period of 25 years and in some circumstance within 10 years. The findings support previous research that shows cavity wall insulation firms are not adequately assessing each property before recommending the work, putting homes at risk. It also indicates that even when houses are suitable some companies are failing to follow best practices to deliver the results they should.
Understanding when cavity wall insulation is suitable can be a challenge but homeowners should be able to rely on those in the sector. For example, homes in areas that frequently experience wind-driven rain should not be recommended cavity wall insulation as it can result in the insulation material becoming damp and holding water, leading to long-term problems if left untreated.
The report, which was put together by construction research organisation BRE, called for a national survey to full assess the extent of the unintended consequences and a review of current practices and guidance within the industry. The recommendations following the report suggest that the organisation believes the issues could be far reaching and affecting a significant number of homes.