For questions about exhaust fans -- i.e. fans used to remove air from specific rooms in a building and exhaust it to the outside in order to control humidity and/or combustion products. Exhaust fans, unlike [ceiling-fan]s, are installed into the building's structure, either in a fitting within the room's ceiling, or remotely, drawing air from the room via a duct and grille.
Questions tagged [exhaust-fan]
433 questions
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Does a bathroom exhaust fan have to vent to the outside?
Is it normal and/or code compliant to have a bathroom exhaust fan venting to the attic?
I've seen this a couple times now, and the first time I saw this I thought it was very odd.
But I mentioned this to a couple people around here and they thought…
dark fader
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Bathroom exhaust fan without duct
I just found out that our bathroom exhaust fan has no duct attached to it. Our current fan is Panasonic FV-08VQ2 (90 CFM, 4" duct diameter). The fan just blows the air to the inaccessible attic. There is what looks like an attic exhaust close to the…
user2503795
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Exhaust fumes seeping into our 4th floor apartment at night through bathroom and shower vents/fans
This is our second fall/winter in our 4th floor apartment, and we've noticed that whenever the weather becomes cool, exhaust fumes which seem to come from the garage in the basement of the apartment building, seep into our apartment through the…
sheg
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What is the purpose of a bathroom exhaust fan?
Okay I actually do understand the purpose of the bathroom fan; it gets the steam out of the bathroom after a super hot shower, right? Well turns out I never turn it on. I suppose I don't shower in sauna temperatures. Also we tend to shower with…
Trout
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Will it cause problems to shower without the exhaust fan and only turn it on afterwards?
If the exhaust fan was not turned on until after the shower is complete (say, 30 min. after the water is first turned on), is that enough to cause mold/mildew/paint issues? The mirror is foggy during these 30 minutes.
Or is 30 minutes of humidity…
kostmo
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Can I vent my bathroom exhaust fan into a plumbing drain vent?
I installed a bathroom fan in the ceiling. My bathroom is in the room right next to the laundry room. The washing machine has the standard drain pipe vent of a pvc pipe venting to the outside through the roof. To avoid cutting another hole in the…
cmccall
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Is it possible to vent two exhaust fans through a single wall penetration?
I have two bathroom exhaust fans that need to be vented out of the house, but I'd like to do it using a single wall penetration. Is there a code compliant, safe way to do this?
Both bathrooms are on the same level of the house.
There is no…
Tester101
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Why is water leaking near my bathroom's exhaust fan?
This weekend when the snow started melting on my roof, I noticed a small water spot developing around all three bathroom exhaust fans in my house. I'm guessing the water leaked in around the exhaust fan flashing on the roof and ran down the pipe. …
SchwartzE
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What are the pros and cons of soffit vents vs. roof vents?
During my latest foray into the attic, I discovered that my bathroom exhaust fans vent directly into the attic. I'm worried about moisture buildup and I'm considering routing the exhaust to an external vent. How major of an issue is this, and which…
Doresoom
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Should a bathroom fan vent to a separate duct system?
Is it acceptable to route a bathroom exhaust fan to the return of a central air system? I'm afraid this will cause mold to grow in the air return ducts. There is currently a fan in our bathroom and I can't seem to find any separate outlet or vent…
Joel B
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How can I seal the gap around a bathroom exhaust fan?
I've got my exhaust fan installed in the ceiling of the bathroom, now I'm wonder how best to seal the gap around it. The fan housing is obviously sheet metal, and the ceiling has the plastic vapor barrier on top of the drywall. Would metal tape work…
Brad Mace
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Bathroom Fan Replacement With Blown Insulation Above
I would like to replace the bathroom fans that came with my 2019 new construction home. I have successfully replaced the basement bathroom fan and it went well enough. The rest of the fans to be replaced are upstairs, and above them is the attic,…
Michael Sadowsky
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Is it better to vent a bathroom fan out the soffit, the side of the house, or the roof?
Working on a friend's house, we're installing a bathroom fan. He had planned to vent the fan out the closest soffit, which is only a few feet away. I'm trying to persuade him to vent it out the roof at best, or the side of the 2nd floor at worst,…
Karl Katzke
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Bathroom Exhaust Vent - Out Shingle Roof? Or Out Siding?
I'm rebuilding a bathroom and am installing a bathroom exhaust vent since one doesn't exist. My options are to either go out the asphalt shingle roof (Standard Sloped Roof), or, go out the side of the house through the siding.
The bathroom sits in…
RocketManZ
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How can I offset 6" ducting by just a few inches?
I am installing a range hood and due to a ceiling joist in the way, I have to offset the ducting going through the ceiling by about 3" from the center of the hood. I have to do this within about 30" of height from the vent hood to the ceiling. The…
Chad
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