drip edge

Water is always here to the point it's going moldy, and every time it rains it will drip for hours afterwards. Is this normal on a newly constructed flat-roof dormer? Sorry this video is rough: I would really appreciate your thoughts on this. I can give more context to our situation if needed

Hello fellow DIYers, My architects have finished creating the building control drawings for a renovation of my mid-terrace property. One of the details show the coping stone over the side parapet wall for a new single-storey rear extension will cross the boundary due to its drip edge. I have...