Many homes could find themselves impossible to sell or secure a mortgage on because of an emerging crisis over insulation.

The guidance being offered to RPSA members is to adopt a highly cautious approach. Sprayed polyurethane expanding foams are used in the lofts of houses, either to stabilise a failing roof covering, or to provide extra insulation. However where the roof structure contains this material it makes proper inspection difficult and prevents it from being given a clean bill of health.

Unless extremely detailed information about the exact nature of the materials used, the condition of the roof covering and structure prior to the installation, and sophisticated studies of the movement of air and moisture within the living and roof areas of the house are all available at the time of the inspection by the surveyor, it is impossible to recommend anything other than immediate removal of the spray foam. This type of information is rarely, if ever, available.

Research by the RPSA and PCA has concluded that many spray foam installations have been carried out with insufficient preparation to reduce the risk of structural roof timbers being severely weakened by rot and other defects.

Some installers may prey on vulnerable homeowners, and point to certification and ‘quality’ badges to convince people that spray foam will benefit their property. Sadly, the exact opposite is the case. Some owners may find their property difficult, or impossible to sell, when lenders will not offer mortgages or equity release funds due to the perceived risks and, may end up having to spend £000’s replacing their entire roof covering.