Bought a house a few months ago where the roof of a one-story garage meets the wall of a two-story house, like in this image.
Recently noticed that there is mold and a leak in the corner of the garage. Only leaks when it rains reasonably "hard". Directly above it is the roof. First home, and really just now getting into the DIY of it, but upon examining the roof (image below), I'm fairly confident the water is seeping in between the siding and roof of the garage. There doesn't appear to be any flashing, which would explain the water leak.
Would I be able to install flashing on over the shingles, and under the siding, like in this last picture? Assuming I can get under them once I take the 2x6 off, of course. Or, am I going to have to remove the shingles, put flashing down, and replace the shingles?