The invention concerns a wall or roof of a building, wherein at least one heat controlling element for controlling a temperature in the building is arranged in the wall or the roof to form a segment of the wall or roof, the heat controlling element comprising at least a first section and a second section, the first section comprising a heat collecting and storing material and the second section comprising a heat insulating material, wherein the heat controlling element may adopt a first configuration, in which the first section is directed towards the outside of the building and the second section is directed towards the inside of the building, and a second configuration, in which the second section is directed towards the outside of the building and the first section is directed towards the inside of the building.