A roof assembly for a vehicle comprises a stationary part (3) and at least one rigid panel (4) movably supported by the stationary part through an operating mechanism. The panel is movable between a closed position, in which it closes the opening in the fixed roof, and a rear position, in which it is moved with its rear side upwardly and slid rearwardly. A downwardly extending side cover (8) is connected to side edges of said panel (4) and to the stationary part. The side cover hides the operating mechanism from a side view and has front and rear ends. The side cover is substantially stationary in longitudinal direction with respect to the stationary part and is slidably guided in a guide rail (12) on the panel. The guide rail is adapted to guide the side cover in vertical and lateral directions. The guide rail (12) only starts at a distance (A) from the front end of the cover (8) when the panel (4) is in its closed position. This distance (A) is minimally B min and maximally: A max = L - S - B min
wherein:
L = Length of side cover (8)
S = maximum sliding movement of guide rail (12) of panel (4) B min = Minimum overlap between side cover (8) and guide rail (15) in rear position of panel (4).