Hi Carol, I just got mine installed. They are not hooked up yet. My electrician, who is a wonderful guy, has been MIA for a month. I guess the schools electric upgrades come before my modest remodel :) Anyway, now school is about to start and they will be more available so that "Nate" can get over here and wire my stuff. The fan is a 170cfm unit if I recall. The fan is actually made in Germany. The grills are about 8" diameter or so and have a halogen light. I don't think it's too weird that the neighboring bathroom will be vented when the one in use is vented, really. It is a new concept but I think it is ok. I was able to keep the roof vent and hook everything together just fine. I had my brother do the work and he did all ridged ducting because it is more efficient. The vents are about 5' apart. I will probably have 2 switches to the unit because I have 2 doors to enter the room. Fantech is a unit that I have seen referenced many times on GW, with great reviews. When I talked to the tech guy he was very helpful.

Ridgid is really the only way to go especially over long runs. We usually spec 4" sched. 20 PVC pipe as it comes in longer lengths than 4" metal does around here , though elbows can be tough to source sometimes. Unfortunately most contractors / HVAC guys will use flexible corrugated hose because it's cheap and fast. If it's a luxury project they'll splurge for the flex aluminum instead of the plastic kind. This type of pipe can cut a fan' effectiveness in half over long runs. Little thought is really given to these fans in most homes today. They are often undersized for a given bathroom and poorly located too. The crappy pipe detailing makes a bad situation worse. Panasonic's website has (or used to) a pretty good tutorial on how to properly size a fan, where to locate it and how to properly pipe it to the outside. I think much of the problem is cost and ignorance. Most people know you get a fan in your bath , but when pressed they won't really be able to tell you its there to expel warm moist air from your home, not smells. They assume that the $34.95 version will be fine for them and a quick & dirty install will get ya out the door for a hundred bucks. The reality is, many master baths, and some hard working kids baths need a much larger fan than 35 bucks can buy. We are often talking $100-$200 for an adequate model, more if you want features or quietness. Add the increased piping cost and labor for the proper venting needed on higher capacity fans and this can quickly become a $500 line item - which starts to look crazy for something as pedestrian looking as a bath fan. Timer switches are also a very good idea as most fans even properly sized ones need to run a while after you've left the bath to completely exhaust the moist air.

It's a fan so your probably going to hear it but it shouldn't be distracting. I've got a 30" Wolf convection and a Wolf steam oven along w/the 36 BS oven. Of the 3 the steam oven fan is the loudest, the 30" Wolf w/2 fans is 2nd and the BS is probably the quietest but you can hear them all. It probably has more to do w/their location in kitchen as to the relative noise level. The BS, being down low is probably quietest due to it's location behind the island, the steam is the highest oven in the kitchen and also the one we use the most but even it's noise is within acceptable kitchen levels. We can't really hear the D/W except when draining.

We live in a very humid area. I struggled for years keeping up with the mildew. Then I got a squeegee( like you use for windows) and insisted that everyone using the showers would wipe them down after each shower. Magic , no more mildew. Recently when I was ill to squeegee after showering, I had to smile when I found my dear husband squeegeeing the shower for me. Good luck with your new bath! I give thumbs up also to Panasonic's heater, fan, light combo. Well worth the extra money. Check Amazon - great prices on the fan.