A roof assembly for a vehicle, having a roof opening in its fixed roof, comprises at least one movable panel closing said roof opening in its closed position and being movable from said closed position rearwardly and upwardly above the fixed roof. A driven operating mechanism supports the panel and comprises a telescope including a first telescopic part attached to the panel and a second telescopic part attached to a remainder of the operating mechanism. A height adjusting mechanism is provided between the panel and the operating mechanism. This height adjusting mechanism is arranged and adjusts the height between the first and second telescopic parts.