Heat could be coming in around edge of fan unit if there are gaps. There should be a damper attached on the unit and possibly another at the outlet to the outside. Please check my website for impartial remodeling ideas. Mark Here is a link that might be useful: Mark Daniels Kitchen and Bathroom Remodeling

mike -- Don't know that we will need a timer. It's just DH and I -- retired -- can remember to turn it off, I think. BTW, how long should it run after a bath or shower? energy rater -- The specs say the backdraft damper is within the 8" duct connection portion of the fan, not whether it faces in or out. I need to ask that they face it away from the fan itself, right? Or are you saying the damper should be not at the fan, but at the soffit? The bath is on the NW corner of the house. Air and moisture will go UP through the bathroom ceiling into the fan, ACROSS about ten feet of attic floor, then out a West soffit. Is it at the soffit that you want metal-flex flaps? Does moisture acclumlate there? Drip outside the exterior wall? (Yeah, where DOES the water go?) I see round aluminum-looking flex-ducting in the attic. Is that what I should expect to see on this install -- not hard metal ducting like a forced air furnace? Is this capacity appropriate? I want to eliminate excess moisture, but don't want to be taking baths or showers in a wind tunnel! (It is meant to run *while* one bathes and a short while afterwards, right?) Is a sone rating of 1.7 good? Is Broan a good brand? This installer is also going to correct three other, smaller bathroom exhaust fan ducts that now empty INTO the attic instead of outdoors. Price is $900 all in for Broan unit and all work. He says it will take about four hours. We are north of Chicago in a high-*address tax*-suburb, as my DH terms it. Thanks so much for your time and trouble. Much appreciated. I'm probably overly concerned, but we keep finding faults (like these fan exhausts) in a house that passed city inspection when it was built only 10 years ago. I'm sure it was not code to vent into an attic!

Thanks for your thoughts. The vent levers to the outside wall were opening fully when the fan was on, thus eliminating the possibility of 'stuck levers' or any thing disconnected as being the problem. So, I called Broan and spoke with a man who said it sounded like the motor wasn't doing it's job and in spite of the fan being out of warranty, he was very generous in his offer to send a new motor at no cost. I'm a Broan fan for life as a result. On Monday, our handyman is coming to install the new motor and use spray foam around the opening to the attic which should eliminate the 'attic smell'. I think that sealing up this gap will also improve the fan 'draw'. I can always count on my Gardenweb family to come to my rescue ~ thanks for your time ! gardening annie

As for fan-lights in the shower, it seems ineffective to try to remove water vapor laden air from the shower since most of it will condense on the walls before that can happen anyway. My goal is to remove humid air from the vanity area and allow fresh air drawn from the door undercut to reduce fogging of the mirror and window glass. The entire bathroom will eventually dry out if you use a fan with a built in timer and/or constant low speed feature like Panosonic's WhisperGreen series. I have yet to find a fan-light combination that performs as well as separate units. Here are my criteria: no CFL or LED lamps (LED inappropriate in a bathroom; CFL inappropriate in a house) Max sound rating .8 sone max grille size 13x13 flush with ceiling variable speed fan with timer Panasonic makes a recessed spotlight-fan combination (FV08VRL1) but it uses a CFL. I suppose a halogen PAR lamp could be substituted because the CFL is probably only needed to get an EnergyStar rating but I am not comfortable recommending it. To reduce fan noise it is important to reduce back-pressure by using larger metal ducts.