Abstract: A self-propelled construction machine has a machine frame and an operating drum for processing the ground surface, wherein the operating drum is positioned in a downwards open drum housing, that is closed on both sides by an edge protector, which is adjustable in height by an actuator for raising and/or lowering the edge protector. A control unit comprises a sensor for registering the distance a between a reference point on the edge protector and the ground surface. Furthermore, the control unit is configured so that when the distance between reference point and ground surface falls below a predetermined minimum distance, the actuator is switched from a floating setting, so that the edge protector is raised. As a result, the edge protector tightly closes the drum housing at the sides without there being a risk that the edge protector can be entrenched in loose substrate.