Some car manufacturers mount the roof to the chassis within the final assembly line. To achieve a secure joint that can withstand vibrations and prevent against water leakage mostly regular beads are used to mount the roof panels to the chassis. Because the car body is not going through an oven when reaching the final assembly line, mostly 2C adhesive is used.
One of the steps within final assembly is the installation of the cladding/roofing felt. The cladding is glued to the inner of the roof, to make it not only optical appealing but also to dampen the sound whilst car operations.
Mostly the adhesive is applied in parallel rows directly on to the felt and then firmly pressed in to the roof. The parallel rows usually consist of regular 2 component beads. High speed and precise applications are used to achieve this secure and reliable joint.