A superstructure (100; 100') of a drain located in the floor area of a washing or showering area, which is built or is to be built in a wall element, comprising: - a panel-shaped cover flap, - a cover box to be placed over the drain and having a rear wall, a top wall and side walls (18, 18') connected thereto, wherein the cover box has an underside open towards the drain and a front side open towards the interior of the washing or showering area, for receiving the panel-shaped cover flap, - wherein the cover flap has a first and a second visible surface (24; 24'), one of which points outwards in the direction and the other inwards in the direction when mounted, - wherein the cover flap has a bottom edge and, when installed, is aligned approximately perpendicular to a floor surface of the washing or showering area and arranged in such a manner that a drain slot remains below the bottom edge, - wherein cover flap and cover box are detachably coupled to each other via a mounting and the cover flap is movable about an axis of rotation, characterized in that - a latching element (33; 33') is arranged on the cover flap or on the cover box, with which the cover flap can be fixed in a first installation position or in a second installation position in preferably vertical alignment, - the axis of rotation and a suspension element rotatable about the axis of rotation as well as the latching element (33; 33') located below the axis of rotation in the installed state of the cover flap are in each case spaced equidistantly from the first visible surface and the second visible surface so that in the first installation position of the cover flap the first visible surface points in the direction and in the second installation position the second visible surface points in the direction. - a panel-shaped cover flap, - a cover box to be placed over the drain and having a rear wall, a top wall and side walls (18, 18') connected thereto, wherein the cover box has an underside open towards the drain and a front side open towards the interior of the washing or showering area, for receiving the panel-shaped cover flap, - wherein the cover flap has a first and a second visible surface (24; 24'), one of which points outwards in the direction and the other inwards in the direction when mounted, - wherein the cover flap has a bottom edge and, when installed, is aligned approximately perpendicular to a floor surface of the washing or showering area and arranged in such a manner that a drain slot remains below the bottom edge, - wherein cover flap and cover box are detachably coupled to each other via a mounting and the cover flap is movable about an axis of rotation, - a latching element (33; 33') is arranged on the cover flap or on the cover box, with which the cover flap can be fixed in a first installation position or in a second installation position in preferably vertical alignment, - the axis of rotation and a suspension element rotatable about the axis of rotation as well as the latching element (33; 33') located below the axis of rotation in the installed state of the cover flap are in each case spaced equidistantly from the first visible surface and the second visible surface so that in the first installation position of the cover flap the first visible surface points in the direction and in the second installation position the second visible surface points in the direction.