Spray foam insulation: the new mortgage-killer for social tenants

Between approximately 2008 and 2020, hundreds of thousands of UK homes had spray polyurethane foam (SPF) insulation installed in their lofts, often free, under government energy-efficiency grant schemes (CERT, ECO, the Green Deal, then Green Homes Grant).

It was sold as a wonder product. It's now a documented problem, and if you're a social tenant in a property with it, the implications go beyond your own household.

What is spray foam insulation?

Two main types: open-cell (softer, more permeable) and closed-cell (denser, water-resistant). Both are sprayed as a liquid that expands and hardens, filling the gaps between rafters in a loft space.

When applied correctly, it's an effective insulator. When applied incorrectly, and a significant proportion was, it traps moisture against timber, prevents the loft from being inspected, and damages the structure of the roof itself.

Why mortgage lenders care

Spray foam came to prominence in the mortgage industry around 2022. Major lenders including Nationwide, Lloyds, Halifax, NatWest, and TSB started refusing mortgage applications on properties with SPF, even on Help to Buy and Right to Buy purchases.

Their reasoning:

• The foam can't be inspected for hidden damp without removal
• Removal is expensive (£5,000-£15,000)
• If the foam has caused roof damage, the property may need a full re-roof
• Surveyors can't certify what they can't see

The Royal Institution of Chartered Surveyors (RICS) published guidance in 2023 advising surveyors to flag spray foam as a potential defect. The result: thousands of properties have become effectively unsaleable.

Why this matters if you rent

If you're a social tenant in a property with spray foam, you might think this is a problem for the landlord, not you. There are three ways it becomes your problem:

1. Right to Buy / Right to Acquire

If you've been considering exercising your Right to Buy (council tenants) or Right to Acquire (housing association tenants), spray foam could kill your mortgage application. Even if the council/HA sells you the property, a mortgage lender may refuse to lend on it. You'd need cash, which most Right to Buy applicants don't have.

This is a real loss of housing opportunity caused by the landlord's installation decision.

2. Hidden damp

The most common SPF failure pattern: moisture trapped between the foam and the underside of the roof timbers. You don't see it until the timber rots. By that point, the damage is structural.

If you've got unexplained damp patches on bedroom ceilings or top-floor walls, and there's spray foam in your loft, the two are likely linked. Your landlord has a duty under Section 11 to address structural defects, regardless of who originally installed the insulation.

3. Heat loss when SPF degrades

SPF degrades over time, particularly when wet. As it degrades, its insulation value drops sharply. Your heating bills rise. If your landlord installed it under an energy-efficiency grant scheme on the promise of warmer, cheaper-to-heat homes, the degradation is a breach of that implicit promise.

What to do if you have spray foam

Step 1: Confirm it's there. Look up into your loft. Closed-cell SPF is hard and yellowish. Open-cell is softer and lighter coloured. If you can see it covering the underside of the roof tiles or between rafters, that's it.

Step 2: Photograph everything. Date-stamped photos from multiple angles. Note any visible discolouration, sagging, or damage.

Step 3: Check for damp. Look at top-floor ceilings and walls for patches, mould, or staining. Photograph those too.

Step 4: Write to the landlord. Cite:

• Their duty under Section 11 of the Landlord and Tenant Act 1985 to keep the structure in repair
• Their duty under the Homes (Fitness for Human Habitation) Act 2018 to ensure the property is fit
• If you can prove the SPF was installed under a government scheme, the implicit warranty that comes with it
• Awaab's Law if the damp is causing health symptoms

Demand a survey by a contractor experienced in spray-foam (SPF) removal (not just a generic roofer, they need to assess the SPF specifically).

Step 5: If the landlord refuses or delays. This is where a claim comes in. SPF cases are increasingly common; we've seen settlements of £3,000-£15,000 covering inspection costs, remediation works, and compensation for loss of mortgage opportunity.

The right to claim is the same whether or not you'd planned to buy

You don't have to be exercising Right to Buy to have a claim. The structural-defect duty is independent of any future sale plans. A spray foam claim can run on the basis of hidden damp, heat loss, and degraded property condition alone.

Useful sources

• RICS guidance on spray foam, search "spray foam insulation"
• The Property Care Association's SPF inspection register, independently certified specialists
• The original government Green Deal scheme documents for proof of installation

Get an honest assessment

If you've got spray foam and you're worried about damp, mortgage prospects, or heating costs, call us free on 0800 030 4669 or start a claim online. We'll tell you honestly whether you've got a claim worth pursuing or whether the right route is a direct surveyor inspection paid for by the landlord under their existing repair duties.

Support For Tenants is a trading name of Cyntex Group Ltd, authorised and regulated by the Financial Conduct Authority as a Claims Management Company. FRN 1020217. Registered in England and Wales.