Treated lumber and OSB is a known adhesion issue with closed cell. ACQ and CA copper-based treatments can inhibit adhesion significantly. Lapolla tech bulletin actually warns about this. Your fix: prime with a water-based primer before foam application on any treated material. For OSB specifically, I now always ask the GC if it is treated before quoting. If it is, I add 15 percent for primer cost and time.
Treated lumber and OSB is a known adhesion issue with closed cell. ACQ and CA copper-based treatments can inhibit adhesion significantly. Lapolla tech bulletin actually warns about this. Your fix: prime with a water-based primer before foam application on any treated material. For OSB specifically, I now always ask the GC if it is treated before quoting. If it is, I add 15 percent for primer cost and time.