The polyurethane foam I'm talking about is used to fill the lacuna between two layers of fiberglass in a boat building. It is a closed cell foam, so it does not absorb water. I need a small amount, 50-60 l of expanded foam. I hope to find it as a spray, that is my next errand.
Mike, I'm actually planning to go to Poland for some spare parts for my trailer. But I'm searching for a small package of foam as a spray, and industry like Jan's is using large machines. I doubt I could use it my case.