The Residential Property Surveyors Association said there may be as many as 250,000 homes with attic spray foam insulation
A financial adviser said he noticed the problem two years ago when clients came to him and said they had been told they could not sell or remortgage their property after an appraiser’s appraisal.
Hundreds of thousands of homeowners who have had spray foam installed in their attics could find their properties worthless unless they spend thousands of pounds to remove it.
Andy Wilson, an equity release specialist, said customers found the problem was with the foam insulation installed in their roof.
He said: “One client who came to see me was devastated because the surveyor had shown him a form of where they were [the surveyor] had valued the property at £0. They were told this was because they had foam insulation installed in their roof.”
Spray foam insulation has been used for about 30 years but has grown in popularity over the past decade.
It was included in the Government’s Green Homes Grant, awarded to homeowners in England to help fund certain energy efficient home improvements.
Though it closed to new applications on March 31, the grant allowed homeowners to reclaim at least two-thirds of the cost of some energy-efficient renovations. The maximum amount available was £10,000.
The Residential Property Surveyors Association (RPSA) said there may be as many as 250,000 homes with attic spray foam insulation. It said the guidance being offered to its members was to “take an extremely cautious approach and recommend removal of the spray foam in almost every case”.
Mr Wilson said the foam insulation used in attics should not be confused with cavity wall insulation.
The type of foam insulation used in attics is polyurethane foam (SPF). He said: “It is also known as spray foam or spray polyurethane foam (SPF), this is an alternative to traditional building insulation such as fiberglass, wool or mineral fiber rolls. It can be used to insulate your roof, attic, walls and floor – but it’s the roof installation that causes UK mortgage lenders particular problems.”
The foam is applied in liquid form using powered sprayers, which then expand and become a solid coating.
There are two types of spray foam insulation, open cell spray foam insulation and closed cell spray foam insulation.
The problem is with the closed-cell spray foam, said Mr. Wilson. “Because it seals the roof space with this material, airflow can be restricted to the roof and the joists. This can cause condensation, which can eventually rot the wooden roof trusses.”
“The closed-cell foam version also cures very hard. This can also stress the supporting roof beams and lead to deformation of the roof itself.”
This means that lenders are reluctant to mortgage a property with the insulation.
Mr Wilson said: “The foam comes with a guarantee but the guarantee does not cover any damage it may cause.
“Also, the fact is that the foam may not have caused any damage, but the only surefire solution is to have the foam removed.”
Removing the insulation is likely to be more expensive than installing it. Mr Wilson said: “The material being sprayed gets into all the crevices and gaps behind the timbers, making access and removal difficult. However, not all lenders will be happy to accept the property for a mortgage. This is because the damage may already have been done.
“Some modern forms of foam may not do any harm – but it will do little to change the mortgage situation until lenders and appraisers start accepting all the evidence presented that it is indeed safe to use.” Until it can be proven, the advice will be to remove it.”
Mr Wilson said a client of his paid nearly £4,000 to have the foam professionally applied under the roof of their three-bedroom Lincolnshire family home.
“There are a number of mortgage lenders who might accept this – but all will require a referral to them before proceeding and will usually require appraiser approval and meet certain criteria as to the type and material used. In our experience, the closed-cell formulation is the most important. This can be a problem when you have to pay to see a surveyor only to find that they turn the property down.”
Alan Milstein, chairman of the RPSA, said it had conducted a comprehensive review of the spray foam and said it was impossible to recommend anything other than removing the spray foam immediately. He added, “And in our experience, that kind of information is rarely, if ever, available.”
Mr Milstein said: “Although we wanted to identify the circumstances in which surveyors could give a sound certificate of health to a roof in the presence of spray foam, our research concluded that most spray foam installations were undertaken with inadequate preparation to reduce the risk of structural damage to diminish roof beams, greatly weakened by rot and other defects.”
He said: “Installers often prey on vulnerable homeowners, citing certifications and ‘quality’ badges to convince people spray foam is benefiting their property. Unfortunately, exactly the opposite is the case. Owners can find their property difficult or impossible to sell, lenders not offering mortgages or equity funding and risk having to spend £1,000 to replace their entire roof covering.”
Christopher Hough, 67 from Blaby, Leicestershire had spray foam installed in his home in 2018.