Principality Building Society's Current Stance on Spray Foam
If you've applied for a mortgage or remortgage with Principality Building Society and been told your property is unmortgageable due to spray foam insulation, you're not alone. Principality — one of the UK's largest building societies and the biggest in Wales — applies strict criteria to properties where spray foam has been installed in the loft or roof space. In practical terms, this means many applicants find their application stalled or declined at the survey stage, often without a clear explanation of what needs to happen next.
The Principality Building Society spray foam problem is not unique to this lender, but Principality's underwriting team has become increasingly firm in recent years. Their valuers are instructed to flag any evidence of spray foam during inspection, and in most cases this triggers a retention, a decline, or a requirement for further specialist assessment before any offer will proceed.
Understanding exactly what Principality's position means — and what you can do about it — is the first step to moving forward.
Why Lenders Like Principality Restrict Spray Foam Properties
To understand Principality's policy, it helps to understand the technical problem spray foam creates for lenders and their appointed surveyors.
Spray foam insulation, when applied directly to the underside of roof timbers, bonds to the structural fabric of the building. This creates a range of concerns that are difficult to assess without specialist inspection:
- Concealed timber condition: Once spray foam is applied, surveyors cannot visually inspect the roof timbers beneath it. Any rot, beetle infestation, or structural movement is effectively hidden from a standard RICS valuation survey.
- Moisture entrapment: Closed-cell spray foam in particular can prevent timbers from breathing, trapping moisture and accelerating decay over time — often without any visible external signs.
- Removal complexity: Unlike loose-fill or blanket insulation, spray foam cannot be simply lifted out. Its removal requires specialist equipment and expertise, and if carried out incorrectly it can cause damage to the very timbers it was bonded to.
- Reinstatement costs: Lenders are concerned about the potential cost to reinstate a property in the event of repossession. Where spray foam has been poorly installed or has begun to deteriorate, those costs can be significant and uncertain.
Principality, like most mainstream lenders, instructs its valuers to treat these risks conservatively. Their obligation is to protect the security of the loan, and a property with unassessed spray foam represents an unknown liability.
The Role of Professional Surveys in Mortgage Applications
When Principality's valuer flags spray foam during an inspection, the lender will typically request one of the following before proceeding: a specialist spray foam survey, confirmation that the foam has been removed, or both.
A specialist spray foam survey goes beyond a standard RICS Level 2 or Level 3 report. It involves a detailed assessment of the type of foam installed, its condition, the extent of application, any evidence of moisture damage or structural compromise, and a recommendation on whether removal is required. Critically, it must be carried out by a surveyor or assessor with specific knowledge of spray foam behaviour — a general building surveyor without that background will not produce a report that satisfies Principality's underwriting requirements.
This is an important distinction that many homeowners miss. Obtaining any survey is not enough. The documentation needs to meet a defined standard that lenders and their appointed valuers will actually accept.
Is Removal Necessary? Understanding Principality's Requirements
Not every property with spray foam will automatically require full removal before Principality will lend. The outcome depends on several factors:
- The type of foam — open-cell or closed-cell
- The age of the installation and its current condition
- Whether the foam was applied by a professional installer with documented warranties
- The findings of a specialist survey regarding timber condition
In practice, however, industry experience suggests that Principality and similar lenders will decline to proceed in the majority of cases unless removal is confirmed and evidenced. Where a specialist survey concludes that the foam is in good condition and the timbers are sound, there is occasionally scope for the lender to accept a retention or proceed with additional conditions — but this is the exception rather than the rule.
For homeowners looking to sell, remortgage, or release equity, the most reliable route to a clean mortgage offer is professionally documented removal carried out to a recognised standard.
A Realistic Scenario: Sarah in Cardiff
Sarah owns a semi-detached property in Cardiff and approached Principality to remortgage and release equity for home improvements. Her application progressed smoothly until Principality's valuer visited and noted spray foam insulation in the loft. The valuation was returned with a nil value against the security and a note requiring specialist assessment.
Sarah obtained a survey from a local building surveyor, but Principality's underwriting team rejected it — the surveyor had no documented specialism in spray foam and the report did not address the specific criteria the lender required. After a further six weeks, Sarah engaged a specialist contractor who carried out removal, produced a full post-removal timber inspection report, and issued a completion certificate aligned with the EBR-01 standard. Principality accepted the documentation and her remortgage completed shortly afterwards.
Sarah's experience is typical. The delay and additional cost were largely the result of engaging the wrong professional at the outset.
How EBR-01 Certification Provides Assurance to Lenders
This is where the industry has developed a clear and practical solution. EBR-01 is the UK's independent Code of Conduct for spray foam insulation removal, established to create a consistent, documented, and technically rigorous standard for the removal process. It exists specifically to bridge the gap between what lenders require and what the market has historically struggled to provide consistently.
When a contractor operating under the EBR-01 framework carries out a removal, the process generates a structured body of documentation: a pre-removal survey report, a record of the removal methodology used, a post-removal timber condition assessment, and a completion certificate confirming the work was carried out in compliance with the Code. This documentation package is designed to satisfy the risk-mitigation requirements of mainstream mortgage lenders and to be accepted by RICS-qualified surveyors carrying out valuations on behalf of those lenders.
Only EBR-01 certified contractors produce documentation that UK mortgage lenders and RICS surveyors recognise as meeting this standard. This is not a commercial claim — it reflects the practical reality that lenders need assurance not just that foam has been removed, but that the removal was carried out safely, that timbers have been assessed post-removal, and that there is a clear audit trail if questions arise later.
For Principality specifically, presenting removal documentation produced under the EBR-01 framework gives the underwriting team the confidence they need to proceed. It removes the ambiguity that so often causes applications to stall.
To find a contractor operating under this standard, visit the