Selling a house with spray foam insulation

Spray foam in the loft doesn't make a house unsellable, but it does need handling properly. Sales most often stall when the foam is discovered late – by the buyer's surveyor or the lender's valuer, weeks into the process. The steps below are about getting ahead of that.

1. Find out what you've actually got

Look (or ask someone to look) at the underside of the roof. Note whether the foam feels soft and spongy (open-cell) or hard and rigid (closed-cell), whether it covers the timbers, and whether there's felt or a membrane behind it or it's sprayed straight onto the tiles or slates. Photos help. These are the same things a surveyor will record under the industry inspection protocol.

2. Gather the paperwork

The joint industry Spray Foam Customer Guidance says a complete handover pack should include a pre-installation roof evaluation, a hygrothermal (moisture risk) evaluation, the product's BBA or Kiwa certificate, and the installer's details, credentials and any guarantee. If you don't have it, government guidance says the installer or manufacturer should be able to provide it retrospectively. The Insulation Manufacturers Association says paperwork showing a correct, professional installation should be enough for a knowledgeable surveyor or lender in many cases.

If the foam was installed under a government scheme since 2020, it should have been fitted by a TrustMark-registered installer – your paperwork will name the installer and scheme provider. See our mortgage guide for the TrustMark dispute and insurance-backed guarantee routes.

3. Disclose it – the forms ask directly

Standard property information forms now ask the question outright. The Conveyancing Association's BASPI form asks whether spray foam insulation has been installed and, if so, for details and the compliance certificate, and the Law Society's TA6 form (6th edition) covers it too. BASPI reminds sellers that under the Consumer Protection from Unfair Trading Regulations 2008 anything that would materially affect an average buyer's decision must be disclosed during marketing. Leaving it out tends to backfire when the buyer's surveyor finds it anyway.

4. Consider a survey before you list

An independent spray foam assessment before marketing lets you answer buyers' questions with a report rather than a guess. If the surveyor concludes the installation doesn't significantly increase risk, that report can travel with the sale. If they recommend removal or remedial work, you'll know early and can choose whether to do the work, price it in, or negotiate. Published guides put an assessment report at around £250–£600 – see our cost guide.

5. Help your buyer's lender

A buyer's mortgage depends on their lender, not yours. In October 2026 the government said many lenders are open to lending on homes with spray foam, subject to their own requirements, naming Nationwide, Lloyds, Santander, Barclays, NatWest, Coventry Building Society, the Co-operative Bank and HSBC. Encourage buyers to tell their broker about the foam at the start, and give their surveyor the paperwork and your report.

Should you remove it before selling?

Only if an independent specialist recommends it. Government guidance warns that removal won't always guarantee a lender will lend, and that improper removal can cause further problems. If you do remove it, make sure the contractor provides before-and-after photos, a timber inspection and a completion certificate for your buyer's surveyor.

Buying a house with spray foam?

Ask the seller for the paperwork above, tell your lender or broker early, and ask your surveyor whether they're familiar with the March 2023 inspection protocol. RICS says that if you're buying a property with spray foam you should make sure the documentation is available, as it will help with questions from the valuer, lender and solicitors.

Related guides

• Spray foam & mortgages
• Removal costs
• Spray foam & equity release
• Is spray foam insulation bad?
• Spray foam surveys explained