Abstract: Brickwork near the outer ends of horizontal coke ovens which forms vertical heating flues in heating walls is renewed by a method wherein the oven chambers at opposite sides of the heating wall are partitioned by vertical walls. These vertical walls are located at a point inwardly in the oven chambers so that a vertical cut can be made through the oven wall of the innermost heating flue to be repaired. The brickwork in front of the vertical cut is then pulled down. New parts for the oven wall are connected to existing parts by oven bricks which have a lug that is arranged when installed so that the lug extends along the heating flue side to engage over existing oven bricks.