A luminous module for mounting in a household appliance has a housing that is embodied in such a way as to receive a luminous element. A through-loading opening is provided in the element. A cover layer is formed on the base insulating layer to cover a predetermined portion of the conductor layer. A combined height of bricks scheduled over time is monitored. The alignment guide or cutting guide may be modified to correct for an existing joint problem, for example an incorrect alignment of the joint.