A friend of mine had the same issue with his new toy hauler. What we did was to add a piece of sheet metal, found at home supply stores. This was shaped so that you would attach it to the body of the TH, it sticks out so as to go over the top edge of the door, and has a little part of the flashing that faces downward. This catches the ran and diverts it out beyond the closed door and the rain falls harmlessly out beyond the door. This was not what is normally called "drip edge flashing", it's shaped differently. The top edge of the photo will be the part that attaches to the TH. We had to trim the height of this edge to make it fit, , ,
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