Spray foam and lenders

Spray foam is only in the lean-to roof, and the main loft is quilt. Do lenders still ask their own question?

Yes. Lenders ask what their own criteria require, and a lean-to is still a roof with foam in it. A quilted main loft means those rafters could be seen, but it does not turn the lean-to into an unfoamed house. RICS does not say every lender refuses foam, or that a partial installation is invisible to a valuer, so ask the lender you are using.

Last reviewed 24 October 2026. Written for buyers in England and Wales unless this answer says otherwise. No named surveyor has signed this page. It is general guidance, not a report on your house, and not legal advice.

What is the fuller explanation?

RICS’s consumer guide explains that foam sprayed under a covering can hide the timbers, and that an undetected leak can then rot the wood. In a lean-to, the hidden timbers are the lean-to rafters, not the main roof you could see from the hatch. Say that clearly. A mortgage valuation is a different document from your home survey, and the valuer or the lender may still ask what was sprayed, where, and by whom. Your surveyor’s sentence is the accurate description to pass on: foam in the lean-to; main loft insulated with a quilt and rafters visible. Do not shorten it to “no foam” because the main loft was clear.

Do not assume this lender will refuse, and do not assume they will ignore the lean-to because it is small. Both guesses go beyond the RICS guide. Ask the lender with the survey wording in front of you. The seller’s paperwork, if any, should be requested for the lean-to specifically. A guarantee for a different roof is not this one. Removal, if anyone later proposes it, can damage tiles. That fact belongs in the conversation with a roofer. It is not a conclusion the home survey has already instructed.

What should you ask your surveyor?

Which roofs have foam, and which rafters could you actually see?
Did foam stop you inspecting the lean-to structure?
Are you saying a lender will refuse? Please keep their decision out of your sentence.

What are the typical next steps?

Tell the lender foam is in the lean-to and the main loft is quilt, in those words.
Ask the seller for any specification for the lean-to job.
Do not market the roof to yourself as foam-free.

Costs vary with the building and with who you instruct. Where this page does not cite a published figure, ask the surveyor, a relevant specialist, or your solicitor for a written quote. Do not treat a forum average as the price.

Also asked about this

Does a quilt in the main loft identify the product used in the lean-to?

No. The quilt does not identify the foam. Do not guess the product from the other roof.

Is a lean-to too small for a lender to care?

You cannot know from the survey. Ask that lender. Small is not a category in the RICS guide.