Principality Building Society and spray foam insulation
Our contractors: 15,123 verified reviews across 8 platforms, rated 4.9 on GooglePrincipality Building Society is reported to be among the lenders that will not currently lend on a property with spray foam in the roof, regardless of the foam's condition. That position was last verified in September 2026 and is not published by Principality itself, so have a broker confirm it before you plan around it.
Principality Building Society's reported position
Principality is named in broker sources and trade press among the building societies that decline spray foam cases outright, consistent with the BBC's November 2024 survey, which found around a quarter of the UK's largest providers would not lend on a foamed roof at all. Principality does not publish spray foam criteria, so this is a reported position, last verified September 2026, not a quoted policy.
What this means for you
A Welsh building society with a broadly conservative lending book, Principality is reported to apply the same exclusion whether the case is a first-time buyer, a remortgage or a like-for-like transfer. That matters because it removes the usual lever people reach for first, a good specialist report, since a blanket policy is not designed to be argued with property by property.
If Principality holds your current mortgage or is the lender your buyer has approached, the practical question is less about the roof and more about whether the mortgage can move somewhere that will look at the evidence. Get the roof looked at either way, because the answer to whether it needs to come out matters regardless of which lender ends up assessing it.
This is not Principality's published policy. No lender publishes its spray foam criteria, so treat this as a starting point, last verified September 2026, and confirm the current position with a broker before acting on it.
What to do next
The same three routes apply, weighted the same way.
- Inspect first. Free, and it tells you whether you have a documentation problem or a real one. The Property Care Association's own inspections found no defect in around two thirds of over 500 lofts.
- Remove and document if the foam needs to go, so the evidence pack works with any future lender, not only the one currently declining.
- Ask a broker for a lender that assesses case by case. With Principality reported to decline consistently, this is usually the quicker fix than waiting on an exception.
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Get the loft looked at properly
Whatever your lender's position, the starting point is the same: know what is actually up there. An inspection gives you a written verdict and photographs, and if the foam is sound that is what the report says.
Book the free inspection
Two steps. No deposit, and nothing to pay if the foam is sound.
Principality Building Society and spray foam, common questions
Will Principality accept a Property Care Association inspection report?
Not according to reported broker experience. Case-by-case lenders are the ones reported to weigh a specialist report; a blanket-refuse position like this one is not designed to be overturned by documentation alone.
Does this apply to Principality's buy-to-let lending too?
Reported experience does not draw a clear distinction between residential and buy-to-let cases. Ask a broker to check the specific product, since policies can differ by lending arm even within one lender.
Is Principality likely to soften this position soon?
There is no sign of that as of September 2026. Government engagement with lenders has continued through 2025 and 2026, including a ministerial roundtable in March 2026, but press coverage in July 2026 still described the underlying problem as growing rather than easing.
What is the fastest way to check Principality's current stance?
A broker who places spray foam cases regularly, or your conveyancer raising it with Principality directly in writing. Do not rely on any single published table, ours included, without confirming it against your specific case.
Does Principality's position apply to shared ownership or new-build purchases too?
Reported broker experience does not identify an exception for shared ownership or new-build purchases specifically. The exclusion is described as tied to the presence of spray foam in the roof itself, regardless of the purchase route.
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