What is the correct way to insulate a below grade basement wall. I have applied the rigid fiberglass board against the interior wall and have fired it out with 2 x 4's. The insulation board goes from about 1" above the floor up to top of the block wall. A relative tells me this is not good, that in preventing the heat from the inside to penetrate through the wall to the outside, the ground outside will freeze too solidly and cause the wall to crack. Is this something I should be concerned about?