Good that you realize the soffit issue with an exhaust vent. Either block off the soffit on each side from above, or could you possibly replace some of the vented soffit from below with solid material? There are higher quality roof vent hoods available. Fantech or American-Aldes are two sources that I've used. A roof vent can be added without damaging the integrity of the roof, just pay attention to the details and work carefully. Are the prevailing winds in your favor to limit snow accumulation in the proposed location? While your at it, consider adding a fan timer at the wall switch to insure the required ventilation time it takes to remove all the bath moisture.

Babka: ha. they (fixtures) are vented to the space above, (which is under the stairs), not to the outside - which is against the code, I know that much. I guess they (whoever added this bath) ran into the same problem with venting fixtures as we are facing trying to figure how to vent the exhaust fan. and maybe that's why there is no exhaust fan to start with. The bathroom is under the staircase whichi s in the middle of the house, and there is space directly above it because the ceiling is short. But then the ceiling height changes as you go to any neighboring room (the rest of the house around has much higher ceilings). Basically, you can put the duct vertically through the ceiling above the bathroom, but then as you turn it 90 degrees towards in the direction of any outside wall, it would have to come out through the wall of any room around, not in the ceiling above the rooms. And if you try to go higher with the duct so that the turn is at the level of the over-the-ceiling space for these rooms, then the duct would have to come out through the staircase! Hard to explain, but I hope you go the picture. Also, even if we could somehow get the duct to the space over the ceiling of any adjacent wall, then we still can't open up that high ceiling to run the duct further because it has some fancy beams and moldings (house is over 100years old) so we cannot touch the ceiling. That's why I wrote "absolutely no way" for the ceiling route Unless, as somebody above suggested, we place the fan in the ceiling, but run the duct through the wall down to under the house (actually through the under-the-stailrcase part as the stairs go down). But as far as I understand that comment, we will have to install some inline fans in the duct to keep the air moving down...

I have been searching High and Low for a replacement motor for my AUPU Bath Master Exhaust Fan - Model A716. It is the same as the Aero Pure A716. Neither AUPU nor Aero Pure have been responsive to my inquiries. If I need to replace the whole unit I will not buy an AUPU or Aero Pure.

Bathroom fans are rated in "sones," and you want to get one that has the lowest sone number for your money. Sometimes you have to dig into the specs a bit to find this, but that spec, plus the reliability of the brand, are the key factors. Cheap fans will have high sone numbers and the quieter ones typically cost more. I agree with numbersjunkie that Panasonic makes good, and quiet, fans. Here is a link that provides some general info on sizing and noise levels: Bath fans Other factors to be aware of are making sure that: 1) the vent duct is of adequate size per the manufacturers specs, and 2) the fan exhausts to the outside, not just into your attic or ceiling space. If the ducting is small and/or you have an extremely long run, it can make the fan sound noisier, and be less efficient. If you don't exhaust to the outside, you could end up with moisture damage and mold. It's not uncommon for builders or subsequent owners to skip the ductwork if they can get away with it, so it's always good to check this.