I am in upstate NY and have maybe an inch of snow on the roof. Some water is dripping from a bathroom exhaust fan. Not a whole lot, but some. I expect it is inadequate flashing on the vent, but I know the roofer will blame it on condensation, and it just might be. Any great way to tell the difference?
Two years ago water was coming in from improper flashing on the chimney when it rained hard. The roof said it was due to moisture from the bathroom 40' away condensing. He eventually repaired the flashing and paid for the ceiling repair. Haven't had "condensation" since. This problem is not quite so obvious.
The roof is 7 years old with a 10 year warranty. When I complained about the chimney flashing he told me he didn't care about the warranty; leaks happen and he is not responsible. It took a while to convince him the warranty was a legal document. The pity was that until then I was pretty happy with his work. Oh well.