Im going to put up 2" XPS foam on the walls, frame it with 2X3 24" O.C. and later drywall it. Basement is 9' high, 5' underground. I was told to adhere the XPS to the walls to avoid any air movements but walls are not flat. Walls were also sprayed with some kind of a granular substance which will make more difficult adhering the XPS to the walls.
Any advice what kind of adhesive to use to get the XPS sticking to the wall without air gaps?? If this is not possible should I use a vapor barrier between the walls and the foam?