I am installing a recessed bathroom fan/light combo in my bathroom and the only place it can be put (due to joists and spacing) makes the vent for the blower about a 16 inches away from the plywood of the roof. I have been trying to google over and over but I always find people who are making ducts too LONG. In this scenerio could it be too short? There is currently no hole and it has been vented into the attic for the past 47 years (the fan it is replacing is from 1970). The roof is vented at the top of it and at the soffits so I cannot go out the soffit, correct? In a perfect world I would like 0 cold air blowing into the bathroom and no condensation falling on me while I am on the toilet I live in Michigan so the winters get cold. If it is any help it is a North facing roof at what looks like a 26 degree pitch. Thanks.