Why Is Spray Foam Insulation a Problem for Remortgaging?
Spray foam insulation has become a significant concern for mortgage lenders due to a combination of technical, structural, and surveying issues. Understanding these concerns is important for homeowners trying to navigate the remortgage process.
Concealment of roof timbers
When spray foam is applied to the underside of a roof, it coats the rafters, battens, and underside of the tiles or slates. This makes it impossible for a surveyor to visually inspect the roof timbers for defects such as rot, woodworm, or structural damage. Lenders rely on their surveyors to assess the condition of the property, and if key structural elements cannot be seen, the surveyor cannot give a confident assessment.
Moisture and ventilation concerns
Traditional pitched roofs are designed to allow a certain amount of air circulation through the roof space. Spray foam insulation, particularly closed-cell varieties, can disrupt this ventilation by sealing the roof space. This can trap moisture, potentially leading to condensation, timber rot, and damage to the roof structure over time. If the roof tiles or slates need to be replaced, spray foam can make this process significantly more difficult and expensive.
Tile and slate adhesion
Spray foam can bond to the underside of roof tiles and slates, making individual tile replacement extremely difficult. Tiles that normally sit on battens and can be easily lifted and replaced become fixed in place, which complicates maintenance and roof repairs.
Surveyor concerns
The Royal Institution of Chartered Surveyors has raised concerns about spray foam insulation in roof spaces. Many surveyors will flag spray foam in their valuation reports, and some will provide a nil valuation or advise the lender that they cannot adequately assess the roof structure. This can lead to the remortgage application being declined.
Difficulty of removal
Once spray foam has been applied, removing it is extremely difficult, time-consuming, and expensive. The foam bonds tightly to surfaces and removing it can damage the underlying materials. This means that homeowners cannot simply reverse the installation if it causes lending problems.
Types of Spray Foam and Lender Attitudes
Not all spray foam insulation is viewed the same way by lenders. Understanding the differences between the types can help you assess your situation and communicate effectively with potential lenders.
Open-cell spray foam
Open-cell spray foam is softer, more flexible, and allows some degree of moisture vapour transmission. It is generally considered less problematic than closed-cell foam because it is easier to remove if needed and is less likely to trap moisture against the roof structure. Some lenders may be more willing to consider properties with open-cell spray foam, particularly if it has been installed to a recognised standard.
Closed-cell spray foam
Closed-cell spray foam is denser, more rigid, and creates a complete vapour barrier. While it provides higher insulation values, it is more likely to cause ventilation and moisture issues in roof spaces. It is also much harder to remove and more likely to damage underlying surfaces during removal. Most lender concerns about spray foam relate primarily to closed-cell varieties applied in roof spaces.
Location matters
The location of the spray foam in your property is a critical factor. Spray foam applied to the underside of a pitched roof is the most problematic scenario, as it conceals the roof timbers and can affect ventilation. Spray foam applied to walls, floors, or flat roofs may be viewed differently, as these installations do not typically prevent structural inspection in the same way.
Installation quality and standards
The quality of the installation also matters. Spray foam installed by a reputable company that is a member of a recognised trade body, carried out to appropriate standards, and accompanied by a guarantee or warranty may be viewed more favourably than an installation with no documentation or quality assurance. Some installers are now offering BBA (British Board of Agrement) certified systems, which may give lenders more confidence.
The Current Lending Landscape
The lending landscape for properties with spray foam insulation has been evolving, and it is important to understand the current position to set realistic expectations for your remortgage.
Lenders who decline spray foam properties
A significant number of lenders currently decline mortgage applications on properties where spray foam has been applied to the roof space. This includes several major high street names who have adopted cautious policies in response to surveyor concerns and industry guidance. For these lenders, the inability to inspect the roof timbers is a fundamental barrier.
Lenders who may consider spray foam
A growing number of lenders are willing to consider properties with spray foam insulation, subject to certain conditions. These conditions typically include having a professional survey or inspection confirming the condition of the roof timbers, evidence that the installation was carried out to an appropriate standard, confirmation that ventilation has not been compromised, and in some cases, a guarantee from the installer covering the installation for a specified period.
Product transfers as an alternative
If you are already with a lender and struggling to remortgage to a new provider, a product transfer with your existing lender may be an option. A product transfer allows you to move to a new deal with your current lender without a full remortgage application or valuation. This sidesteps the spray foam issue entirely, though the range of products available may be more limited than the wider market.
Industry developments
The mortgage and surveying industries are actively working on solutions to the spray foam issue. New survey methods, including thermal imaging and timber condition assessments through the foam, are being developed. Trade bodies representing spray foam installers are also working with lenders to establish standards and certifications that could increase lender acceptance over time.