flat roof addition leaking
My son bought a house that has a one story addition the end of 2 story house, and where the lower roof attaches, it slopes until it reaches a window in the second floor where they made it flat so it wouldn't come above the level of the window. The flat area is about 3'x6'. Apparently water can stand there and leaks down through the wall and makes the floor damp in the addition. They are removing damp wall-to-wall carpet and putting more down, but I am concerned that the drainage and leaking be repaired first. How would this be accomplished?