Mandy Hutson thought she was doing her bit for the planet. In 2021, the customer operations manager, 53, installed spray-foam insulation in the loft of her four-bedroom 1980s house in Newport Pagnell, Buckinghamshire. She had never heard of spray foam but saw it as an option in the government’s Green Homes Grant.
“The proviso was that I had to use an approved TrustMark supplier. I found an approved company, who sent a surveyor to check it could be installed safely. I sent in the quotes and the government issued me a voucher. I had the foam installed in May 2021. I paid £1,843 and the government paid £3,686.”
She was pleased when her heating bills decreased, and recommended the product to her mother, Sue, 74, who lived nearby in a two-bedroom 1970s bungalow, and also had it installed.
The loft in Hutson’s home
VICKI COUCHMAN FOR THE SUNDAY TIMES
But the family had a rude awakening in February, when Mandy tried to sell her property. “I had an interested buyer. But their mortgage company told them they would not lend against the house because I had spray foam in the loft. I provided the warranty for the foam but they wouldn’t accept that.”
Mandy’s estate agent recommended she have the foam removed, but Mandy was quoted £8,000. “I don’t have that kind of money knocking around,” she says. “But if I don’t have it removed, I’ve heard horror stories about possible damage to the roof.”
So Mandy took her home off the market. Her mum, a retired events organiser who is thinking of downsizing, feels similarly stuck. “We had the house valued. The estate agent was horrified when they heard I had the foam in the loft.”
Mandy and Sue are not alone. An estimated 250,000 homeowners in Britain have spray-foam insulation in their loft, according to the Property Care Association (PCA), a trade body for building specialists. However, the industry has been plagued by cowboy installers, whose poor quality installations can leave moisture trapped behind the foam and rotted roof timbers.
Even if the roof is not damaged, it can be difficult for surveyors to declare it safe, because they can’t see the timbers behind the foam. As a result of this uncertainty, lenders may refuse to provide mortgages, leaving some homeowners unable to sell or remortgage their homes.
The industry and surveyors have been trying to break the impasse. In March 2023, the PCA introduced the Sprayed Foam Insulation Inspection Protocol, an attempt to establish uniform standards for surveyors to assess whether roofs with foam are at risk. Since then the PCA has been providing specialist training for surveyors to inspect foam-lined roofs. There are presently nine professionals trained to provide risk assessments for homeowners, with more on the way, according to James Berry, the deputy chief executive of the PCA.
“I haven’t got any doubt that some lenders will provide finance if the foam was installed correctly,” says Stephen Hodgson, a building consultant and former chief executive of the PCA who now inspects spray-foamed roofs for homeowners and trains surveyors. “But the vast majority of installations that my colleagues and I are looking at are problematic and never should have been done. There are defects.”
Of the 45 inspections Hodgson estimates he’s done in the past year, he reckons only three were done properly and would pass muster with lenders.
Hodgson is finding three common problems. One, lofts that already had insulation on the floor now also have spray foam on the underside of the roof. Having both poses a condensation risk, he says.
The second issue is that the majority of installations he sees are sprayed onto roofs already lined with bitumen felt membranes (non-breathable or “high-resistance underlays”), typical of most UK houses built between 1900 and 1960. “If you install something that allows vapour through — ‘breathable’ open-cell foam — and then back it with something that isn’t breathable, like bitumen, the vapour goes through the foam, stops and gets wet,” says Hodgson, who is also a fellow of the Chartered Association of Building Engineers. “That’s when the risk of decay occurs.”
The third problem is the quality of installations. “Many have holes and inconsistencies in the foam. That creates cold patches where water builds up.”
An estimated 250,000 homeowners in Britain have spray-foam insulation in their loft
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New research echoes surveyors’ concerns. In April, the government’s Health and Safety Executive released a report on the moisture risk of spray foam applied to timber roofs. Its modelling predicted the risks are “high” when open-cell spray foam is applied directly onto the underside of the roof. And the report predicted that in some of the modelled scenarios, 25 per cent of the timber would decay over a five-year period in roofs where open-cell spray foam is applied to a high-resistance underlay such as a bitumen felt.
Risks were deemed low when open-cell foam is applied in line with official guidance — for example with a breathable underlay or an air gap behind it. The problem, Hodgson says, is that for a long time “the industry has ignored its own guidance”.
That said, homeowners should not panic and rush to have their spray foam insulation removed, Hodgson cautions. Many of the cowboy companies that installed such insulation have dissolved and reinvented themselves as removal companies, charging £5,000 to £10,000. Some do shoddy jobs that leave you no better off. He advises to wait until the panic — and prices — die down. “In some circumstances you can leave it alone: if it’s a newer house and foam is built into the roof with a vapour barrier on the warm side, for instance.”
If, however, your house was built before the 1960s, with foam sprayed directly onto the roof, or on to a bitumen felt, “you should be thinking about taking that out at some point,” Hodgson adds.
If you need to sell imminently, assemble your paperwork and call the PCA for advice and a possible risk assessment survey to show lenders.
If you opt to have it removed, first research the history of the removal company on Companies House. If they were previously an installation company, they may not be trustworthy.
• We can’t sell our house because it has spray-foam insulation
You may have no choice but to remove it if you want equity release on your house, says Andy Wilson, director of Andy Wilson Financial Services, an equity release specialist in Lincolnshire. “All lifetime mortgage lenders still will not lend on properties with foam in place,” he says.
“One lender, LiveMore, has introduced a lifetime mortgage that can be taken out even if the foam is installed, on condition it is removed within 90 days of completion of the loan. This product will help those who are unable to finance removal up front. But it has higher interest rates than alternative providers.”
Wilson has been able to obtain equity release for clients who had their spray foam removed using the Hampshire-based extraction companies Vac-Xtract and Britt & Co.
One of Wilson’s clients was Geoff Shaw, a retired oil distribution director, 81, who in 2021 paid a cold caller £7,250 to have foam installed on his 1990s bungalow in North Yorkshire, but was later refused equity release. So he paid £9,960 to have it removed, and in 2022 sought compensation from Hydrogard Legal Services on a no-win, no-fee basis. “Last week £17,210 was refunded to my credit card account. Hydrogard will shortly get a well-earned 30 per cent of the recovery figure. I am grateful for their efforts.”
Simon Baker, president of Huntsman Building Solutions, a global manufacturer of spray foam insulation based in Texas, warns against using cold callers. “There are a number of unscrupulous installers, and not all installs are the same … We only sell to authorised contractors and we make sure they have been through our Huntsman Building Solutions University.” (The company runs five-day installation courses in the UK, in Norfolk.)
Baker disagrees with some of the findings of the Health and Safety Executive’s report, and insists open-cell spray foam applied to non-breathable membranes is approved in certain scenarios, for instance if moisture surveys are performed. “The UK needs more insulation, and spray foam is one of the best solutions,” he says. “We have been operating in North America for more than 40 years.”
Some believe traditional floor insulation is a less risky option for your loft
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Can he guarantee his customers will receive a mortgage if they have spray foam? “It’s impossible to guarantee. But we’ll work with the lender and the surveyor to make sure that the foam is correctly understood. We’ve found a huge lack of understanding around spray foam in the surveyor community. When we educate, there’s a lot more acceptance of it… It’s not as difficult to get mortgages as it’s portrayed to be. We find 999 out of 1,000 times, homeowners can get a mortgage, once the documentation is explained.”
Hodgson concedes foam can be a great insulator, but doesn’t believe installing it in a cold, uninhabited loft space is worth the risk. He believes traditional loft floor insulation is cheaper, just as efficient and keeps lofts ventilated and timbers dry. And he says UK homes are built differently than North American ones.
Paula Higgins, chief executive of the HomeOwners Alliance, says the industry needs better regulation. “The installation companies should be up front with customers that if you have foam installed, you may not be able to get a mortgage.”
The installation of spray foam in uninhabited loft spaces is not supported in the government’s latest green retrofit scheme, the Great British Insulation Scheme. But that’s too late for Mandy Hutson. “I think it’s disgusting that the government recommended something and walked away,” she says.
A Department for Energy Security and Net Zero spokesperson said: “All spray foam insulation funded by any government grant must be installed by a Trustmark registered company. It is the certified installer’s responsibility to recommend an appropriate product that meets the standards required. The government consulted installers, lenders and surveyors, who have now published protocols to allow an assessment of spray foam installations to provide reassurance to lenders.”