Ok, so when was the last time you were on the roof of your RV? Did you know that inspecting your roof is an extremely important step to maintaining your RV?
Closely inspect the roof coat condition on every protruding fixture, any cracks or thin spots can be touched up with the appropriate material. If the roof coat is peeling or flaking in any way, then the old coating must be removed by scraping it off. On metal roofs I use a 1″ wide scraper with a firm blade, like the ones used by auto technicians for scraping off old gaskets. For rubber roofs I made a plastic scraper that won’t cut the membrane. If you heat the old coating with a hot air gun, it will come off fairly easily.
For metal roofs, use the aluminum roof coat, available in gray or white, and brush it on about 1/8″ thick. Stir very thoroughly and apply on a warm day for the best results. For rubber, use elastomeric roof coating that is safe for rubber roofs or the special self leveling sealant sold at RV supply stores for this purpose. Never use a petroleum based product on a rubber roof as damage to the rubber membrane will result. Also, while silicone chalking has a place in the RV, it has no place on the roof. Silicone will not stick well and may damage the rubber, and on a metal roof it will adhere to some places and not others causing pockets that will trap water.