Spray foam insulation has left an estimated 250,000 UK homeowners unable to remortgage or sell their properties, with a quarter of major lenders refusing to lend on affected homes. This guide explains the mortgage risk, the impact on energy grants, removal costs, and the steps to take in 2026.
What Is Spray Foam Insulation and Why Is It Controversial
Spray foaminsulationis a material that is applied as a liquid and then expands into a solid foam, filling gaps and creating an airtight barrier. It has been used in UK homes for decades, but it became far more common after it was funded through government energy schemes in the early 2020s. The result is that a significant number of UKhomeownersnow live in properties that have spray foam in the roof space, often without having chosen it themselves or having been fully informed of the longer-term implications.
The controversy centres on one core problem: spray foam bonds to roof timbers and roof coverings. Because it is difficult or impossible to inspect the underlying timber once foam is in place, mortgage surveyors appointed by lenders have no way to assess whether the roof structure is sound. That uncertainty has caused a large proportion of mortgage lenders to decline applications on properties with spray foaminsulation, making affected homes difficult to sell or remortgage.
This guide explains the full picture in 2026, including which lenders are affected, what removal costs look like, how spray foam interacts with energy grants, and what steps to take if your home has it.
How Spray Foam Ended Up in So Many UK Homes
The majority of spray foam installations in UK lofts were not a consumer choice. They were carried out under government-backed energy efficiency programmes, primarily the Green Homes Grant scheme, which ran from 2020 to 2021, and through council and social landlord schemes in subsequent years.
Installers promoted spray foam as a quick and effective way to insulate a loft or roof, and the government funding made it cost nothing for many households. What installers did not always make clear was the impact on mortgage valuations, the difficulty of subsequent roof inspections, and the potential for condensation problems if the foam was not correctly matched to the property type.
The Parliamentary Library has produced a briefing on spray foaminsulationand mortgages, noting that the issue has been raised repeatedly in Parliament and that the government has been in ongoing discussion with the mortgage industry about how to address the problem. A government meeting took place in March 2026 at which lenders agreed to continue working towards a solution, though no financial remedy had been announced at that point.
The Mortgage Problem in 2026
The central practical problem with spray foaminsulationis that it reduces your pool of potential mortgage lenders dramatically.
According to research published by the HomeOwners Alliance and reported by the BBC in November 2024, a quarter of the UK's biggest mortgage providers and all equity release lenders surveyed would not lend against homes with spray foaminsulationin the roof. By 2026 the situation remains similar, with major high street lenders including Halifax, Nationwide, Barclays, Santander, NatWest and HSBC known to restrict lending on affected properties.
The reason lenders take this position is a valuation risk problem, not a safety problem per se. When a surveyor visits a property, they need to be able to inspect the condition of the roof timbers. Spray foam makes that impossible. If the timber has rotted underneath the foam, or if condensation has been trapped, the surveyor cannot confirm the roof is sound. Rather than accept that risk, many lenders simply decline the application.
This creates a practical ceiling on the value of your home and on your ability to refinance. If you need to sell and the buyer requires a mortgage from one of the major lenders, the sale is likely to fall through at the survey stage.
Equity Release
The situation is even more acute for equity release. All the major equity release lenders surveyed by the HomeOwners Alliance declined to lend on properties with spray foam in the roof. Since equity release is a product designed for olderhomeownersin properties with significant equity, this is a significant barrier for a cohort of people who had spray foam installed through free government schemes and now cannot access the value in their homes.
The Defect Problem
Mortgage refusal is one issue. Structural damage is another.
The Property Care Association and the HomeOwners Alliance wrote jointly to the government in May 2025 citing inspection data from more than 500 properties. According to that letter, 35% of inspected properties showed one or more defect attributed to or associated with the spray foam installation. Common problems included:
- Condensation trapped between the foam and the roof covering, accelerating timber decay
- Spray foam applied directly to roof tiles or felt without adequate vapour control
- Poorly prepared surfaces causing the foam to de-bond and sag over time
- Roof timbers that cannot be inspected or treated if a problem develops
The risk is higher in certain property types. Older properties with traditional pitched roofs and timber battens are particularly vulnerable if the foam was applied in an open-cell or incorrectly specified closed-cell form.
Open-Cell vs Closed-Cell Spray Foam
Not all spray foam is identical, and the distinction matters when assessing risk and removal cost.
Open-cell spray foam is softer, more flexible, and less dense. It is the more common type used in UK loft spaces and is generally easier to remove. However, it is also more permeable to moisture, which makes it more prone to trapping condensation against roof timbers.
Closed-cell spray foam is denser and more rigid. It has a higher R-value per centimetre, meaning better thermal performance per unit of thickness. It is also less permeable to moisture. However, it bonds more aggressively to surfaces, which means removal is more disruptive and expensive.
When assessing a property, a surveyor or specialist will identify which type is present and whether the application was appropriate for the roof type and construction.
How Spray Foam Affects Energy Grant Applications
Spray foaminsulationcan complicate access to several of the main energy grant routes available in 2026.
Warm Homes Local Grant
TheWarm Homes Local Grantis available to eligiblehomeownersin England with a household income below £36,000 and a property with an EPC rating of D to G. It can fund up to £15,000 of improvements includinginsulation,heat pumps,solar panels, and other energy efficiency measures.
Spray foam in a loft does not automatically disqualify a property from theWarm Homes Local Grant. However, a surveyor visiting under the scheme will assess whether the existinginsulationis performing correctly. If the spray foam has caused roof damage or moisture problems, those issues will need to be addressed before further insulation measures can be funded. In some cases, removing the spray foam and replacing it with conventional mineral wool may be required as part of the remediation process before the property can benefit from the grant.
Local authority delivery of theWarm Homes Local Grantvaries, and eligibility decisions are made by the administering council. If you think your property might be affected, contact your local council directly to ask how they handle spray foam properties in their assessment process.
Loft Insulation Top-Up
A common scenario is a property that has spray foam covering the joists in a loft, making it impossible to top up with mineral wool or blown fibre as part of a laterinsulationimprovement. Standard loft insulation grants, including those available through theWarm Homes Local Grant, cannot simply be added on top of spray foam. If the spray foam is performing correctly and the roof is sound, a surveyor may be satisfied. If not, removal will be needed first.
Boiler Upgrade Scheme
TheBoiler Upgrade Schemeprovides grants of £7,500 towards the cost of anair sourceor ground sourceheat pump, or £5,000 towards a biomass boiler. For off-gas-grid properties, an enhanced grant of £9,000 is available from 21 July 2026 until 31 March 2027.
Spray foaminsulationdoes not directly prevent an application under theBoiler Upgrade Scheme. The scheme requires a valid EPC and an MCS-certified installer, and the BUS does not specify loft insulation type as an eligibility condition. However, spray foam problems that have caused roof damage could affect a surveyor's view of the property's suitability for certain upgrades, and if the EPC assessment reveals significant building fabric issues, the overall eligibility picture could be affected.
Spray Foam Removal Costs in 2026
If removal is the route you choose, costs vary considerably depending on the size of the roof space, the type of foam, and whether the roof covering or membrane has been damaged and needs to be replaced.
For a standard semi-detached home with a typical loft area, removal typically costs between £4,500 and £7,500 for open-cell foam. Closed-cell foam is harder to remove and often costs more, with many specialist contractors quoting in the range of £6,000 to £12,000 for a similar property size.
Published guides from contractors and trade publications place the broad cost range at £2,500 at the lower end for a small property with accessible, open-cell foam, rising to £15,000 or more for a larger property with closed-cell foam that has bonded into roof timbers or tiles.
Cost per square metre is typically:
- Open-cell foam removal: £28 to £35 per square metre
- Closed-cell foam removal: £45 to £60 per square metre
These figures do not include any roof repair or re-felting work that may be required if the foam has damaged the existing roof covering.
There is currently no government grant specifically for spray foam removal. The government confirmed in March 2025 that no financial assistance would be provided for removal costs, though discussions with the mortgage industry continue. As of July 2026, no new removal funding has been announced.
What to Do If Your Home Has Spray Foam Insulation
The first step is to find out what type of foam is present and whether there are any associated problems. Do not commission a survey from a company that also offers removal services, as they have a commercial interest in recommending removal. Instead, use an independent RICS-accredited surveyor or a specialist approved by the Property Care Association to carry out an objective assessment.
The assessment should cover:
- Identifying whether the foam is open-cell or closed-cell
- Checking for condensation or moisture damage to roof timbers
- Assessing whether the foam has de-bonded or is causing structural concerns
- Providing a written report that can be shared with mortgage lenders or estate agents
If the survey finds no defects and the foam is performing correctly, some lenders may accept the property on the basis of the report. The mortgage market for spray foam properties is not uniformly closed, and some specialist mortgage brokers have access to lenders who will consider applications with independent survey evidence.
If removal is recommended, obtain at least three quotes from PCA-member contractors and be clear about whether the cost includes any roof repair. Check whether your home insurance covers any incidental damage during removal, and clarify the scope of work in writing before any contractor begins.
Selling a Home With Spray Foam Insulation
Selling is possible but requires careful preparation. The estate agent should be told about the spray foam at the outset so that buyers are not surprised at the survey stage, which leads to fall-throughs and wasted costs on both sides.
Some buyers will walk away. Others, particularly cash buyers or those using lenders who are more flexible, will proceed. Being transparent, having an independent RICS survey report ready, and pricing the property to reflect the additional risk and potential removal cost for the buyer will give the sale the best chance of completing.
If you are selling through a solicitor, the Law Society TA6 property information form requires you to disclose spray foaminsulationas a material fact about the property.
Spray Foam and the Future Regulatory Picture
The government has been under pressure from MPs, the HomeOwners Alliance, and consumer groups to resolve the spray foam mortgage problem. The core ask is that lenders should be required to consider properties where spray foam was installed under a government scheme as a funded energy efficiency measure, not as a structural risk.
Progress was made at a government and lender working group in March 2026, with further meetings scheduled for mid-2026 to assess whether a framework for conditional lending can be agreed. Whether this leads to concrete lender policy changes remains to be seen, but the direction of travel is toward a more nuanced position from lenders rather than blanket refusal.
Homeowners who had spray foam installed through a government-backed scheme, and can evidence this, are in a slightly stronger position than those who paid for it privately, because there is at least a documented trail that the installation was funded and intended to improve the property's energy efficiency.
Checking Your EPC and Next Steps
If you are not sure whether your home has spray foaminsulation, a chartered surveyor or your EPC assessor can advise. The EPC register at gov.uk allows you to view the most recent energy performance certificate for your property, which may note spray foam in the loft as an existing measure.
If you are considering any grant-funded energy improvements includingheat pumps,insulationtop-ups, orsolar panels, it is worth checking the loft condition first. Ahomeownersassessment that identifies and resolves a spray foam issue before you apply for grant funding will save time and prevent delays in the grant process.
The team at Cucumber Eco work withhomeownersacross England and Wales to identify the right route through the grants landscape. If your property has spray foam and you are uncertain whether you can still qualify for funding, get in touch for an honest assessment before you start any application.
