An electrically operated actuator for operating a window sash of a roof window which is pivotally suspended from a window frame by a horizontal pivot axis and, said actuator being configured to pivot said window sash such that it is positioned in one of an open position zone, a near closed position zone, and a visually closed position zone, a compressible seal or gasket being provided between said window frame and said window sash such that it bridges at least a part of said visually closed position zone, said actuator comprising a position sensor detecting the position of said window sash, said actuator comprising an electronic control unit controlling the operation of said actuator by means of an electric drive motor, said electronic control unit being configured to monitor an electric current directly consumed by said electric drive motor, and/or to calculate and monitor a rate of change over time in said electric current consumed by said electric drive motor, said electric current or said rate of change in said electric current being an indicator of a closing force applied onto said window sash by said actuator, said actuator being adapted to perform a first closing operation while said electronic control unit monitors said indicator of a closing force, said actuator further being adapted to initiate a first reversing operation upon said indicator of closing force exceeding a threshold during said first closing operation, and said actuator being configured to initiate a subsequent, second closing operation after said first reversing operation, monitoring of said indicator of closing force being disengaged when said window sash reaches said visually closed position zone. said actuator being configured to pivot said window sash such that it is positioned in one of an open position zone, a near closed position zone, and a visually closed position zone, a compressible seal or gasket being provided between said window frame and said window sash such that it bridges at least a part of said visually closed position zone, said actuator comprising a position sensor detecting the position of said window sash, said actuator comprising an electronic control unit controlling the operation of said actuator by means of an electric drive motor, said electronic control unit being configured to monitor an electric current directly consumed by said electric drive motor, and/or to calculate and monitor a rate of change over time in said electric current consumed by said electric drive motor, said electric current or said rate of change in said electric current being an indicator of a closing force applied onto said window sash by said actuator, said actuator being adapted to perform a first closing operation while said electronic control unit monitors said indicator of a closing force, said actuator further being adapted to initiate a first reversing operation upon said indicator of closing force exceeding a threshold during said first closing operation, and said actuator being configured to initiate a subsequent, second closing operation after said first reversing operation, monitoring of said indicator of closing force being disengaged when said window sash reaches said visually closed position zone.