Abstract: A device for utilizing a surface, such as the surface of a floor, outside wall or roof, for a variable function, including a first functional element with an active surface area the size of at least a part of the surface, at least one second functional element with an active surface area the size of at least a part of the surface, and a rotatable carrier for varying, on at least a part of the surface, the functional element with which the surface is utilized. A method for utilizing a surface for a variable function is also shown.