Solar Panel L Brackets

Mena, I wrote that 3 screws is the minimum, in my opinion. Not 5. If you don't plan to make solar your main or the only source of energy, then messing with tilt is not worth the trouble. For a flat install, if you don't need to clear some luggage rails, plumbing vents etc, and can get away with 2" or 3" high brackets, you should be alright with 3 deck screws per bracket. For a flat install with small panels and 2" brackets I would think 2 screws per bracket is enough if you hit the rafters, and 3 screws if you don't.