InSite | Spray foam insulation (roofs)

Spray foam insulation (roofs)

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As you may be aware, spray foam insulations are available on the market and are occasionally specified for application to the underside of new and existing pitched roofs. These most commonly consist of either open or closed cell polyurethane. In the past, certain products have been acceptable for warranty purposes, providing that there was full third party product certification and the product was applied with careful consideration and design. Some products, particularly closed cell variants are even specified as a stabilisation method for weak or failing roof coverings. Such applications we would never accept.




Over recent years, spray foams have become a topic of debate with their use and building defects such as condensation issues and associated defects have been reported.  Also, there has been significant conjecture over the use of sprayed polyurethane (PU) foams in domestic property leading to confusion amongst surveyors and valuers about how to report on the condition of a roof with sprayed foam applied to the underside of the roof covering, and with some lenders refusing to offer mortgages on affected properties.


In a bid to address the issue, the Property Care Association (PCA) and Residential Property Surveyors Association led a consultation on the subject in late 2021.


One of the key conclusions issued from this consultation was ‘It is unlikely that a surveyor undertaking a valuation, or a condition survey will be able to provide any advice relating to the condition or life expectancy of the roof structure where the installation of PU foam is not supported by detailed technical information.’ The required level of technical information is considerable.


It also goes on to say that ‘in most situations the professional surveyor will be unable, and ill advised, to comment on the condition of the timber roof structure…..investigations may be lengthy, and will often result in partial or full removal, and irreparable damage to, insulation or roof coverings.’


Warranty stance


Following a review of the joint statement provided by the PCA and continuing lender issues (usually upon re-sale), we have for warranty purposes, taken the decision NOT to accept any spray foam insulations (even products which hold third party accreditation such as BBA) for application to pitched or flat roofs. If this position changes in the future, we will provide an update.


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Every care was taken to ensure the information in this article was correct at the time of publication (September 2022). Guidance provided does not replace the reader’s professional judgement and any construction project should comply with the relevant Building Regulations or applicable technical standards. For the most up to date Premier Guarantee technical guidance please refer to your Risk Management Surveyor and the latest version of the Premier Guarantee Technical Manual.

Ref: TS-3292

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