Wall or roof of a building with at least one heat controlling element

1. Wall or roof of a building, wherein at least one heat controlling element (1) for controlling a temperature in the building is arranged in the wall (W) or the roof to form a segment of the wall (W) or roof, the heat controlling element (1) comprising at least a first section (3) and a second section (4), the first section (3) comprising a heat collecting and storing material and the second section (4) comprising a heat insulating material, wherein the heat controlling element (1) may adopt a first configuration, in which the first section (3) is directed towards the outside of the building and the second section (4) is directed towards the inside of the building, and a second configuration, in which the second section (4) is directed towards the outside of the building and the first section (3) is directed towards the inside of the building,characterized in that the heat collecting and storing material of the heat controlling element (1) may be connected to a metal reinforcement of the building structure (15) by at least one connecting element (16a, 16b) so that there is direct thermal contact between the heat collecting and storing material of the heat controlling element (1) and the metal reinforcement of the building, wherein the connecting element (16a, 16b) is adjustable between a contacting position for providing direct thermal contact between the heat collecting and storing material of the heat controlling element (1) and the metal reinforcement of the building structure (15) and an interrupting position for interrupting direct thermal contact between the heat controlling and storing material of the heat controlling element (1) and the metal reinforcement of the building structure (15).