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

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

It was sold as a wonder product. It is now a documented problem, and for a social tenant in a home that has it, the fallout reaches past your own household.

What is spray foam insulation?

Two main types exist: open-cell, softer and more breathable, and closed-cell, denser and water-resistant. Both spray on as liquid that expands and hardens, filling the gaps between loft rafters.

Applied well, it insulates well. Applied badly, and much of it was, it traps moisture against timber, blocks loft inspections, and damages the roof structure itself.

Why mortgage lenders care

Spray foam hit the mortgage industry's radar around 2022. Major lenders, Nationwide, Lloyds, Halifax, NatWest and TSB among them, began refusing applications on homes with SPF, Help to Buy and Right to Buy purchases included.

Their reasoning:

• The foam cannot be checked for hidden damp without removal
• Removal costs a lot, commonly quoted at £5,000 to £15,000
• Foam that damaged the roof can mean a full re-roof
• Surveyors cannot certify what they cannot see

The Royal Institution of Chartered Surveyors (RICS) told surveyors in 2023 guidance to flag spray foam as a potential defect. The result: thousands of homes turned effectively unsaleable.

Why this matters if you rent

A social tenant might call this the landlord's problem. Three ways it becomes yours:

1. Right to Buy / Right to Acquire

Weighing Right to Buy (council tenants) or Right to Acquire (housing association tenants)? Spray foam can kill the mortgage application. Even with the landlord willing to sell, a lender may refuse the property, leaving cash as the only route, which most applicants do not have.

That is a real lost housing opportunity, caused by the landlord's installation choice.

2. Hidden damp

The most common failure: moisture trapped between foam and roof timbers. Nobody sees it until the timber rots, and by then the damage is structural.

Unexplained damp patches on bedroom ceilings or top-floor walls, with spray foam in the loft above? The two are likely linked. The landlord's Section 11 duty covers structural defects, whoever installed the insulation.

3. Heat loss when SPF degrades

SPF degrades over time, above all when wet, and its insulating value falls sharply as it does. Heating bills rise. Insulation installed on a warm-home promise that now leaks heat undercuts the very point of the scheme.

What to do if you have spray foam

Step 1: confirm it is there. Look into the loft. Closed-cell SPF is hard and yellowish; open-cell softer and lighter. Foam covering the underside of the tiles, or filling between rafters, is it.

Step 2: photograph everything. Dated photos from several angles, noting discolouration, sagging or damage.

Step 3: check for damp. Top-floor ceilings and walls: patches, mould, 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

Ask for a survey by a contractor experienced in SPF removal, not a generic roofer: the foam itself needs assessing.

Step 5: if the landlord refuses or delays. This is where a claim comes in. SPF cases are increasingly common, and a claim can seek the inspection costs, the remedial works, and compensation where a mortgage opportunity was lost.

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

No Right to Buy plan is needed for a claim. The structural-defect duty stands apart from any sale. A spray foam claim can rest on hidden damp, heat loss and degraded 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

Spray foam above you, and worries about damp, mortgages or heating costs? Call us free on 0800 030 4669 or start a claim online. We will say honestly whether a claim is worth pursuing, or whether the right route is a landlord-funded surveyor inspection under the 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.