If the roof is not leaking, I would NOT recommend painting the roof with that stuff.
The best thing to do would be to clean the camper roof well with soap & water.
Let it dry.
Get a small tube of marine grade silicone from the hardware store.
Dab a little of the silicone over each screw head & washer on the roof.
Smooth the silcone around each screw & washer to better seal it up.
Let it dry well.
You should be good to go after that.
OH! I guess only if you have an FWC ?
Not sure what camper you have ?
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