How Do I Know If I Have Spray Foam Insulation?

Nathan

October 1, 2025

Have you recently moved into a property? Or are you looking at selling up or remortgaging? Either way, you might want to consider if you have spray foam insulation and how you would actually know if you have it.

Around 250,000 UK homes are thought to have had spray foam installed, with many of these installed using government-funded schemes such as the Green Homes Grant. However, many mortgage lenders now see spray foam as a problem, which can affect property sales and financing.

The good news if you are looking for any crumb of comfort is the fact that spray foam is fairly easy to spot once you know what you’re looking for. How do I know if I have spray foam insulation? Read on to find out…

What Is Spray Foam Insulation?

Spray foam is an insulating material that gets sprayed in as a liquid before expanding into a thick foam. It creates a barrier, helping stop heat from escaping from roofs, making your home feel warmer, and reducing energy bills.

Instead of being laid in rolls like traditional loft insulation, it sticks directly to the surfaces it’s sprayed onto, filling every gap and crack. While that sounds appealing, especially during the push for more energy-efficient homes, the way spray foam seals everything in so tightly is exactly what causes problems later on.

There are two main types:

Open-cell spray foam: Light and spongy, often used in lofts. You can learn more about this type of spray foam on our service page which includes an open-cell foam identification guide.
Closed-cell spray foam: Much denser and more rigid.

Both can cause similar issues, particularly when it comes to property valuations in the UK.

How to Tell If You Have Spray Foam

Spray foam looks very different from traditional insulation like rolls of fibreglass or mineral wool. Here are the key signs to look out for:

1. Where It’s Found

The easiest place to start is by having a look at your loft or roof space. Spray foam stands out because it doesn’t come in rolls or sheets like traditional insulation. It’s usually sprayed directly onto the underside of roof tiles or slates between the rafters.

Although less common, spray foam is also used in some cavity walls.

2. What It Looks Like

If what you see in your loft looks like it’s been sprayed on and covers everything in a solid layer, rather than being laid down neatly between joists, it’s almost certainly spray foam insulation.

The colour is another giveaway. Most spray foam starts out cream, yellow, or off-white, though it can darken a little as it ages over time. Learn more about the signs of closed-cell insulation on our service page.

3. What It Feels Like

When you touch spray foam, you’ll notice a clear difference too: open-cell foam feels soft and spongy, while closed-cell foam is much firmer and rigid.

Why Spray Foam Insulation Is Problematic

Here in the UK, spray foam insulation has become a sticking point with many lenders and surveyors. In fact, some of the biggest lenders, including TSB Bank, Principality, and Co-operative Bank, won’t lend at all on properties with spray foam present in the roof space.

Others, including Lloyds, Barclays, and Nationwide, may still consider applications, but usually only if you can provide a specialist report confirming that the foam was installed correctly.

So why are lenders cautious of spray foam? The main concerns are:

It can trap moisture, which may damage roof timbers.
It makes it difficult to check the condition of the roof structure.
It can hide roof defects like timber rot.
Some guarantees for roofing work are invalidated once spray foam is applied.

That’s why so many homeowners are now looking into removal. There are simply too many issues caused by poor insulation and spray foam is at the forefront in many of these cases.

Is Spray Foam Insulation Banned in the UK?

Spray foam insulation isn’t banned in the UK, and can still be a highly effective form of insulation when installed correctly in the right circumstances, but it has become a bit of a headache for many homeowners. You can still buy it and have it installed, but the real issue is that having it can make it much harder to sell or remortgage your home.

Spray Foam vs Traditional Insulation

Here’s a quick comparison to make it easier to identify:

Feature	Spray Foam Insulation	Traditional Insulation (Fibreglass/Mineral Wool)
Appearance	Thick foam sprayed directly onto the roof’s underside	Rolls of insulation laid between joists
Colour	Cream, yellow, or white	Pink, yellow, or brown
Texture	Hard or spongy, depending on type	Soft, fibrous, often itchy to the touch
Ventilation Impact	Can block airflow	Allows lofts to breathe
Mortgage Impact	Often flagged as a risk	No known issues

What Should I Do If I Think I Have Spray Foam?

If you’ve identified spray foam insulation in your home, don’t panic. The next step is to have it professionally assessed and, if needed, removed.

Spray foam removal is a specialised job. Attempting it yourself can cause damage to your roof. That said, removal is possible, and once done, it can restore your property’s value and mortgage options.