A sunroof assembly which opens and closes a roof opening portion provided on a roof of a vehicle with a plurality of movable panels and which improves the water proof performance of a vehicle width directional end portions at a clearance between a first movable panel in front and a second movable panel positioned in the rear of the first movable panel. In one embodiment, the separation unit includes a cyclonic separator and a vessel having a flue gas chamber, a clean gas chamber, and an entrained solids chamber between the flue gas chamber and the clean gas chamber. In the selecting step a quality of the web is selected thereby defining a quality selection of absorbency or tear resistance.