I am getting a new roof installed. I got two estimates so far and one roofer wants to install a ridge vent and an electric roof fan (we already have what he calls an inadequate gable fan). I have read on the net that this is not a good thing to do as it can short circuit the attic ventilation system. Shouldn't he know this as a roofer or is this just not the case? The other roofer didn't even suggest it. I have a musty odor in one of my bedrooms and this one roofer is trying to address the problem.