Exhausting Work

Who would think that one of the most difficult decisions we have yet faced would be selecting and locating the bathroom exhaust fan.
The complications started when the plumber mentioned that he didn't think that venting the drier and exhaust fan under the porch would meet the code. I called the building inspector to ask him about requirements for the exhaust fan. "I know there are limits and requirements for drier venting (minimum bends, no screws into the duct, etc. to avoid lint build up which can lead to a fire). What about exhaust fans?" I asked.
He said that the requirements and limits are even stricter for the exhaust fan. The bottom line is they don't work very well. It is better than no ventilation at all, but they simply don't do a great job removing moisture from bathrooms, so you really need to avoid anything that will reduce the efficiency of the fan. Like long duct runs.
Normally an exhaust fan can be located close to an exterior wall, and can be vented right through that wall. In our case, however, the bathroom is not actually adjacent to an exterior wall. It is close, but the laundry area is between the shower and that exterior wall. We figure that the fan will remove steam better if it is located relatively closer to the shower versus closer to the exterior wall. That will mean a longer duct run, though, so we figure we need a somewhat stronger fan than would otherwise be needed for the size of the room.
So we trooped first to Lowe's, where we bought a fan that we later decided was undersized. So I went off to an electrical supply company in Norwood, a nearby town. But they had moved to Canton, on the other side of town. So I stopped at Home Depot and bought a larger fan... but really much larger than we need.
So I actually ended up tracking down the electrical supply house in Canton and buying a THIRD exhaust fan. This turned out to be the Goldilocks fan: not too big, not too small: just right. The lesson is that the big-box stores (Lowe's and Home Depot) may have just about everything... but not necessarily the right size. And of course, the guy behind the counter at the electrical store was actually helpful!