I've seen this only once, and it was with closed cell foam, but I've heard of it happening with open cell foam, too. I don't know the details, but I've heard it could result from a bad batch of chemicals, improper mixing, or too high a temperature. Whatever the cause, it's not a good thing. The photo below shows how the spray foam pulled away from the studs. A little bit of uninsulated area like that adds up to a lot of heat loss/gain when the whole house has that problem, as it did here.
It works 100% as an EPDM rubber coating while also boasting of up to 5-year warranty. Another advantage of this liquid coating is its wide coverage. It comes in a 1-gallon kit, which is capable of covering an area of around 42 to 45 square feet. In addition, it is capable of withstanding a wide range of temperatures – from 6o degrees to 300 degrees Fahrenheit.
Spray Foam Polyurethane