What’s the Controversy Around Spray Foam Insulation?

It was once pitched as a modern insulation miracle: airtight, energy-efficient, and long-lasting. But over the past few years, spray foam insulation has become one of the most controversial building materials in the UK.

So what changed? Why are surveyors, lenders, and even some insurance companies turning their backs on it?

Let’s break down the concerns — and what they mean for homeowners today.

A Quick Recap: What Is Spray Foam?

Spray foam insulation is applied as a liquid that expands into a dense foam. It’s usually sprayed between roof rafters or wall cavities to create an airtight seal.

There are two main types:

• Open-cell – Softer and more breathable
• Closed-cell – Denser, water-resistant, and far more common in older UK installations

While effective in theory, spray foam has proven to be problematic in practice — especially when applied to older properties with timber roofs.

The Core of the Controversy

1. Moisture Trapping
   Spray foam can block ventilation, trap condensation, and encourage timber rot, especially in roofs that were never designed to be sealed.
2. Mortgage Issues
   Many banks and lenders now see spray foam as a structural risk. They’ll often reject properties with it, especially when surveyors can’t inspect the timbers beneath.
3. No Industry Standard
   Thousands of installations were done by sales-led companies with little oversight. As a result, many homes have spray foam but no documentation, no guarantees, and no record of what was used.
4. Difficult to Remove
   Once cured, spray foam bonds tightly to wood, felt, and tiles. Removing it requires specialist tools and care to avoid damaging the structure — and there’s no simple DIY fix.

Real-World Consequences

We regularly speak to homeowners who had no idea spray foam was a problem until:

• A house sale collapsed
• A surveyor flagged it during a remortgage
• A homebuyer asked for it to be removed
• An equity release provider refused to proceed

Many of these people installed spray foam in good faith years ago — often through government-backed schemes or aggressive marketing.

Now, they're being asked to undo it just to move forward.

Can It Be Reversed?

Yes — and for many, it’s the cleanest way to move on.

At Snug & Secure, we carefully remove spray foam insulation, inspect the roof timbers, and reinstall breathable loft insulation that meets modern standards — and doesn’t cause problems for future buyers or lenders.

You can learn more here about our approach and what’s involved.

Should You Worry?

If your home has spray foam, the key question is: Is it stopping you from doing something?

• Trying to sell or remortgage? It probably will.
• Staying long-term with no issues? You might be fine — but keep an eye out for signs of condensation or mould.

If you're unsure, we’re happy to assess the loft and give you straight, no-pressure advice.

Final Thoughts

The spray foam controversy isn’t just media noise — it’s a growing real-world issue for UK homeowners. What was once sold as a modern upgrade is now, in many cases, a barrier to progress.

Whether you’re looking to sell, insulate properly, or just stay compliant, get in touch for honest advice — or browse more guides on our blog.