Hi, My fireplace built circa 70 had a white-painted brick surround. Too bulky and ugly to the point that I could no longer stand it and tore off those bricks. Came with them was the steel lintel and now that the upper opening got exposed to the lower edge of the damper throat. I plan to put the lintel back in and stack a couple of firebricks on top so the opening height can be lowered to the recommended measurement (currently at 32" after the destruction) of 25-30" for a 36" wide fireplace. The problem is if I stack the bricks as typically done (ie. the 4" side flat horizontally), that would make the area bulge out 5" (4" brick width + 1" granite tile + mortar/thinset) from the surrounding wall. I would like this "hanging wall" on top of the lintel to be as thin as possible so that the pre-fab mantel and pilasters do not appear sunk back into the bricks. Will I be meeting fireplace building code for this "opening/hanging wall" if I stack the bricks on their 2" sides so the wall can be 2" thinner? I've looked around the net and haven't seen any specific building code for this particular section of a fireplace. Any suggestions? Thanks much!