A roof assembly for a vehicle comprises a stationary part and at least one rigid panel. The panel is movable between a closed position and a rear position. A downwardly extending side cover is connected to side edges of said panel and to the stationary part. The side cover hides an operating mechanism from a side view and has front and rear ends. The side cover is substantially stationary with respect to the stationary part and is slidably guided in a guide rail. The guide rail only starts at a distance from the front end of the cover when the panel is in its closed position. This distance is minimally Bmin and maximally: Amax=L−S−Bmin wherein: L=Length of side cover S=maximum sliding movement of guide rail of panel Bmin=Minimum overlap between side cover and guide rail in rear position of panel.