Originally Posted by Locutus
Interesting point the author makes about expansion and contraction. I wonder if this issue could cause spray foam to delaminate from the exterior bus skin?
Spray foam is basically plastic. It will contract and expand at the rate of the substrait it was sprayed onto.
So far I have never seen spray foam delaminate from anything. It even sticks to plastic vapor barrier.
I had to do two small demo jobs where a home owner made a big mess of wiring, plumbing, and studs behind a planned kitchen counter.
I started trying to remove individual wires, pipes, ect to make the needed changes. Even using a keyhole saw, utility knife, claw hammer, ect.
It was so hard to get apart, it took 4 times as long. My 10 pound sledge hammer, and the reciprocating saw were the main players. I had to cut the foam vertically between every stud, then smash the studs out with the 10 pound hammer. I had to remove everything they had done because everything was encased in a semi flexible, impact absorbing mass.
If all homes were built with this stuff, they would be 50% stronger. In our blue prints, when a home calls for foamed walls, the engineer will sometimes remover sheeting from interior wind thrust walls due to how stiff the structure becomes.