Still learning the ropes of RV ownership here. Is there a reason that all of the exterior openings (windows, doors) are only caulked across the top of the opening; i.e. no caulk down the sides or across the bottom) Also, is there any reason why I shouldn't add caulk, at least down the sides of the sealed openings? I am thinking about road spray flying up from below when towing in a rain storm and how water can move just about anywhere it has access via capillary action.