Closed cell foam bonded to roof felt
Why it happens here
Closed cell foam is sprayed on wet and sets like adhesive. On Fens roofs it bonds directly to the felt, so cutting it away risks tearing the membrane underneath. That is why so many surveyors flag it as a defect rather than an improvement.
Our approach
We use dry ice blasting to freeze and lift the foam off felt without abrasion, and hand tools on the edges. If the felt is already damaged, we tell you and quote for repair rather than leaving a torn membrane behind.