Operating start method for setting up operation of an automatic building closure designed as a rolling door, which comprises a building closure wing composed of a plurality of segments or slats, which is designed as a roller curtain that can be wound onto and unwound from a winding shaft, a building closure drive device designed as a roller closure drive for driving the winding shaft, which is connected to the building closure wing in such a manner that driving in the closing direction exerts a pushing force exerted in the direction of compressing the segments or slats and driving in the opening direction exerts a pulling force exerted in the direction of pulling apart the segments or slats, and a control unit for controlling a building closure drive unit of the building closure drive device, comprising the step of: a) performing a learning travel in the closing direction for teaching-in a closing end position, wherein step a) comprises: a1) driving the building closure wing in the closing direction, a2) allowing the building closure wing to run up against a mechanical stop in the closing end position, a3) detecting the run-up against the mechanical stop by monitoring a parameter dependent on the drive force in order to detect an exceeding of a force threshold, a4) teaching-in a taught-in closing end position by detecting the position of the building closure wing at which a run-up against the mechanical stop has been detected in step a3) by means of force threshold detection, the steps a1) to a4) being carried out automatically in order to teach-in the taught-in closing end position automatically, characterized in that step a) further comprises a5) selecting, by an operator, a positioned position of the building closure wing offset in the opening direction relative to the taught-in closing end position as the final closing end position, wherein step a5) comprises: a5.1) adjusting a closing end position setting element on the building closure drive or the control unit connected thereto for fine adjustment of the closing end position, and wherein step a5.1) comprises: selecting one of a plurality of predetermined positions of the closing end position setting element to select one of a plurality of discrete predetermined degrees of offset by which the closing end position is offset from the taught-in closing end position in the opening direction. a) performing a learning travel in the closing direction for teaching-in a closing end position, wherein step a) comprises: a1) driving the building closure wing in the closing direction, a2) allowing the building closure wing to run up against a mechanical stop in the closing end position, a3) detecting the run-up against the mechanical stop by monitoring a parameter dependent on the drive force in order to detect an exceeding of a force threshold, a4) teaching-in a taught-in closing end position by detecting the position of the building closure wing at which a run-up against the mechanical stop has been detected in step a3) by means of force threshold detection, the steps a1) to a4) being carried out automatically in order to teach-in the taught-in closing end position automatically, characterized in that step a) further comprises a5) selecting, by an operator, a positioned position of the building closure wing offset in the opening direction relative to the taught-in closing end position as the final closing end position, wherein step a5) comprises: a5.1) adjusting a closing end position setting element on the building closure drive or the control unit connected thereto for fine adjustment of the closing end position, and wherein step a5.1) comprises: selecting one of a plurality of predetermined positions of the closing end position setting element to select one of a plurality of discrete predetermined degrees of offset by which the closing end position is offset from the taught-in closing end position in the opening direction. a1) driving the building closure wing in the closing direction, a2) allowing the building closure wing to run up against a mechanical stop in the closing end position, a3) detecting the run-up against the mechanical stop by monitoring a parameter dependent on the drive force in order to detect an exceeding of a force threshold, a4) teaching-in a taught-in closing end position by detecting the position of the building closure wing at which a run-up against the mechanical stop has been detected in step a3) by means of force threshold detection, the steps a1) to a4) being carried out automatically in order to teach-in the taught-in closing end position automatically, characterized in that step a) further comprises a5) selecting, by an operator, a positioned position of the building closure wing offset in the opening direction relative to the taught-in closing end position as the final closing end position, wherein step a5) comprises: a5.1) adjusting a closing end position setting element on the building closure drive or the control unit connected thereto for fine adjustment of the closing end position, and wherein step a5.1) comprises: selecting one of a plurality of predetermined positions of the closing end position setting element to select one of a plurality of discrete predetermined degrees of offset by which the closing end position is offset from the taught-in closing end position in the opening direction.