Votre-Dame, a cathedral of light.The design of the new roof truss of Notre-Dame is consistent in its external appearance consistently on the proportions of the cathedral, as it was predetermined and planned by the ancient master builders. By reconstructing the crossing tower and restoring the old roof shape, the external appearance is restored. Only the choice of the special construction material makes it clear that the new construction is a timely interpretation. Translucent concrete forms the roof covering and at the same time the roof construction. The heaviness of the concrete fits seamlessly with the massiveness of the natural stone. The precursors of the concrete were already used in the construction of the Pantheon. The translucent concrete also connects the interior and the exterior. During the day, sunlight penetrates through the roof into the interior of the church. The course of the sun as well as the respective cloud cover with changing light conditions can be read. At night and with lighting inside the church, the roof lights up in the night sky. The guiding idea of the Gothic master builders, the pursuit of the light, is to be reinterpreted in this way.This reinterpretation should also be legible in the building. Therefore, the restoration of the former cross vault should be waived. Even the roof truss completely destroyed in the fire is no longer necessary statically and becomes superfluous in the new construction. In the new Votre-Dame, the roof skin represents the interface between the sacred and the outer space. The connection between the earthbound cathedral and the divine heavenly space is thereby emphasized in a special way. The mainspring of the Gothic architects, the conquest of the enclosed space and the pursuit of the light, finds its climax with the increase of the interior.