When flashing goes wrong.
It is always a bad sign when there is a tarp on a roof. Tarps are meant to temporarily keep water off of things. They don't stand up to the hot Phoenix sun. When I saw this tarp I just had to see what was under it.
Here is what I found when I uncovered it.
This flashing must have been a patch just like the tarp was a temporary patch. The vertical flashing should be behind the stucco to catch any moisture that penetrates through. The horizontal flashing should be under the roof tiles. Caulking like this has to be repaired often. The best method of flashing to use here is step flashing.
Here is a diagram of step flashing from NACHI.
The end result of this temporary patch is a large water leak.
If the first leak had been patched properly perhaps all this damage could have been avoided.
Greens Home Design
"Where Art and Building Science Come Together"