Spray foam insulation may look solid, tidy, and energy-efficient from the outside — but to mortgage lenders and surveyors, it’s a serious red flag. Across the UK, perfectly “fine-looking” foam is causing property sales to fall through, remortgage applications to be rejected, and equity release plans to grind to a halt.
If your home has spray foam and you’re wondering why it’s being blocked despite looking intact, this guide is for you.
It’s Not About What Spray Foam Looks Like — It’s What It Hides
Spray foam expands into a rigid or spongy layer (depending on type) that adheres to timber, tiles, and membranes. Once applied, it covers up the structure of your roof.
That’s the problem.
Mortgage lenders rely on surveyors to inspect the property’s condition. And if they can’t visually assess your rafters, beams, or joists, they can’t report on:
Timber integrity
Signs of decay or woodworm
Moisture ingress or trapped damp
Underlying ventilation issues
So regardless of whether your foam is neat or professionally applied, if it hides these areas, it will almost always be flagged.
Even “Well-Installed” Spray Foam Fails the Mortgage Test
Here’s a common scenario:
“We had our loft professionally insulated with spray foam three years ago. The installer said it would boost energy ratings and increase our home’s value. Now, our buyer’s mortgage has been refused — even though the insulation is still in perfect condition.”
This isn’t unusual. Even if the foam:
Was installed by a certified contractor
Shows no signs of sagging or cracks
Is providing great thermal performance
…it can still cause mortgage refusals for two reasons:
1. Lenders Can’t Confirm Structural Safety
No visual access means no report. No report means no lending. It really is that simple.
2. Closed-Cell Foam Traps Moisture
Even if the foam looks dry, it may be hiding condensation, rot, or hidden damp behind it — and that’s enough to make a lender say no.
Surveyors Don’t Care How It Looks — They Need Evidence
What your buyer’s surveyor needs to do:
Check the timbers for decay or movement
Confirm there’s no trapped condensation
Verify that ventilation paths aren’t blocked
If spray foam covers all that, their default response is:
“We recommend removal and a follow-up inspection to confirm structural integrity.”
That leads lenders to one thing: declined application.
What You’ll Hear From Mortgage Lenders
Most lenders have now updated their guidance to brokers. If spray foam is noted on the survey report, you’ll likely be told:
“We cannot proceed unless it is removed.”
“We require confirmation of structural soundness.”
“We need a post-removal report and photos.”
This happens regardless of the foam’s appearance.
How to Get Your Sale or Mortgage Back on Track
If you’re stuck with a failed survey or rejected mortgage, removal is usually the only way forward. But it has to be done right.
Here’s what lenders and surveyors expect:
✅ Full manual spray foam removal (not blasting or solvents)
✅ Clean access to timber and ventilation points
✅ A follow-up inspection report
✅ A spray foam removal certificate with before/after evidence
Anything less — and you risk further delays or another refusal.
Ready to Fix the Problem?
📞 Call us on 020 7870 3965
📧 Or email: team@nationalsprayfoamadvice.co.uk
✅ Free expert consultation | Vetted removal partners | Fast UK-wide support
