What options are there for finishing off at the top of a lean to roof. I've seen some bulky ridge tiles but the angle wouldn't suit the back wall and pitch of the roof. What about cutting lead in the rear of the wall then folding it up and over similar to when a porch is added to the front of a house or any other ideas? I've included a rough sketch to try to show what I mean, it's to prevent rain from the rear and cover the nails of the last row of slate.