Spray foam insulation has long promised better energy efficiency and lower heating bills. But in recent years, growing concerns over how it affects mortgageability, roof ventilation, and timber health have forced many homeowners to ask a difficult question:
Should I remove my spray foam insulation, or is it safe to keep?
The answer depends entirely on your situation — and this honest guide breaks it down clearly.
If You’re Selling or Releasing Equity: It Has to Go
Regardless of how neat or professionally-installed your spray foam is, if you are selling your home, remortgaging, or applying for equity release — the spray foam must be removed.
Surveyors and lenders do not approve of roof structures they cannot inspect, and spray foam almost always hides critical areas like rafters and felt. Worse, it often compromises ventilation, trapping moisture that can lead to rot and decay.
Bottom line: Most UK mortgage lenders will flat-out reject any property with spray foam insulation, unless it’s been professionally removed and certified.
This applies whether you have open-cell or closed-cell foam, whether it was installed properly or not, and even if it looks pristine.
If It Was Installed in the Last 5 Years
Now, if you’re not selling or refinancing, and your spray foam was installed within the past five years by a reputable installer, you likely don’t need to panic.
Assuming:
It was applied correctly to a breathable membrane or vented roof,
There’s no current sign of moisture, condensation, or sagging,
Your roof was well-ventilated beforehand,
…then your foam is likely stable for now.
However — and this is important — even in the best-case scenario, spray foam will still limit airflow within your roof space. Over time, this can lead to condensation or damp issues, particularly if ventilation becomes blocked or if your membrane is damaged.
Best practice: Start planning for ventilation restoration sooner rather than later. This might involve removing small areas of foam or improving air movement in the loft.
You might not need full removal yet, but you should absolutely monitor your roof space carefully — especially through the colder months.
Signs You Might Need to Remove It Anyway
Even if you’re not selling or refinancing, removal may still be the right choice if:
You’ve noticed musty smells, damp patches, or mould in your loft
Your roof space feels humid or lacks airflow
There’s evidence of timber darkening or decay
The foam has degraded, sagged, or discoloured
In these cases, you could be looking at trapped moisture — which can lead to serious structural damage if not addressed.
A survey by a professional removal specialist can help you assess whether action is needed now or can wait.
What If You Decide to Remove It?
If you do choose to remove the spray foam, either now or in preparation for selling, it’s essential to:
Use a specialist removal team (not just a roofer or builder)
Ensure manual removal, not dry ice or chemical stripping
Obtain a full Spray Foam Removal Certificate
Provide before-and-after photos for surveyors
At National Spray Foam Advice, we can help you assess your situation and connect you with vetted, trusted removal professionals near you.
Final Word
Spray foam insulation isn’t always a villain — but it is a serious consideration when it comes to property value, mortgageability, and roof health.
If you plan to sell, remortgage, or release equity: removal is essential.
If your foam is recent, clean, and problem-free: monitor closely, restore ventilation, and plan for the future.
Still unsure? Call us today for free, impartial advice:
020 7870 3965
team@nationalsprayfoamadvice.co.uk
We’ll help you decide what’s right for your home — and your peace of mind.
