We have the standard builder grade exhaust fans in our bathrooms, which we discovered are vented into the soffit on the back of the house. The house was built in 2015. The fans are totally ineffective when it comes to removing the humidity when we shower, they will barely hold a single sheet of toilet paper when they are on. Several times the ceiling has gotten wet from, what I assume, is condensation from the vent pipe. We are going to replace the fans and have them properly vented through the roof. Any advice on picking new fans? Also, any idea on what recourse I would have if we have an attic full of mold? As always, thanks for any insight!
Bathroom exhaust fans
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This is a good resource for what size fan you need: https://www.wikihow.com/Calculate-CFM-for-Bathroom-Fan
I've installed a few of the Panasonics, they are pretty sweet. Get moisture sensing and put them on a timer switch to extend their lives. I would go up there and look to see is there is any mold, but I would replace the affected drywall and look around for mold. If it is localized I would just bleach it and scrape it off and inspect it later. Take a good look at everything up there, just in case they cut any other corners. Inspect again after 6 months or so to see if the mold is gone.
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I'm concerned I'm going to find mold on the roof sheathing. I can't understand why anyone would think warm, moist air is going to flow down to escape a vented soffit. I would think the soffit would push the humidifier air up into the attic
Originally Posted by PW01
I'm concerned I'm going to find mold on the roof sheathing. I can't understand why anyone would think warm, moist air is going to flow down to escape a vented soffit. I would think the soffit would push the humidifier air up into the attic
You might be ok. My father in-law found his disconnect in the attic space when he was up there doing some wiring for a ceiling fan and he had no mold.
I'm concerned I'm going to find mold on the roof sheathing. I can't understand why anyone would think warm, moist air is going to flow down to escape a vented soffit. I would think the soffit would push the humidifier air up into the attic
You might be ok. My father in-law found his disconnect in the attic space when he was up there doing some wiring for a ceiling fan and he had no mold.
I had the same thing in my house which was built in 2003. I went for the top of the line Nutone unit and have been very happy with it. Cant recall the specs, but it moves a lot more air and is whisper quiet. As I remember, it was roughly $120 for just the basic fan, no lights or heater. I would get the same one again. While buying the unit at the store, I saw the builders grade unit there for $15. You get what you pay for.
Putting it on a timer may be a good idea. The new unit is so much quieter than the old one that it occasionally get left on. A timer would eliminate this problem. My suggestion is to buy the best one you can afford.
Putting it on a timer may be a good idea. The new unit is so much quieter than the old one that it occasionally get left on. A timer would eliminate this problem. My suggestion is to buy the best one you can afford.
Originally Posted by Rand
I like a loud fan.. sometimes you need noise to cover up other noise.
This! and for those fans that are not timer controlled - the noise reminds you to shut it off.
I like a loud fan.. sometimes you need noise to cover up other noise.
This! and for those fans that are not timer controlled - the noise reminds you to shut it off.
Originally Posted by KGMtech
Originally Posted by Rand
I like a loud fan.. sometimes you need noise to cover up other noise.
This! and for those fans that are not timer controlled - the noise reminds you to shut it off.
It's best to just wire the fan to the light switch.
Originally Posted by Rand
I like a loud fan.. sometimes you need noise to cover up other noise.
This! and for those fans that are not timer controlled - the noise reminds you to shut it off.
It's best to just wire the fan to the light switch.
https://www.amazon.com/GE-Countdown...;keywords=push+button+timer+light+switch
Having installing a timer switch like this one ( u can find them cheaper) to run the exhaust fan never have to worry about leaving it on or going back to shut it off.
Having installing a timer switch like this one ( u can find them cheaper) to run the exhaust fan never have to worry about leaving it on or going back to shut it off.
I used to have a timer switch but it broke. I mostly didn't want to waste heat by having the fan suck cold air in through the cracks in my outer walls.
Switched to a motion sensor with built-in timer. I leave a "night light" on in the overhead lamp and the main lights and fan come on upon entry, then turn off 90 seconds after exiting.
Now I need one of those Japanese toilets that do everything on that end automatically!
As for your current fan, yes it should blow somewhere outside, not the attic. You can "tune them up" by taking them apart and getting the grime out of there. We don't use hairspray or smoke but still get a bunch of funk in there that slows the squirrel wheel down.
Switched to a motion sensor with built-in timer. I leave a "night light" on in the overhead lamp and the main lights and fan come on upon entry, then turn off 90 seconds after exiting.
Now I need one of those Japanese toilets that do everything on that end automatically!
As for your current fan, yes it should blow somewhere outside, not the attic. You can "tune them up" by taking them apart and getting the grime out of there. We don't use hairspray or smoke but still get a bunch of funk in there that slows the squirrel wheel down.
Is it a good idea to "oversized" the fan? I'm looking at the Broan QT Series for both bathrooms. The hall bath is a bit over 60 sqft so I'm looking at the 80 cfm model, the master bath is about 100 sqft so I'm looking at a 150 cfm unit for it. Good or bad idea?
Originally Posted by JMJNet
As far as fan goes, get a Panasonic exhaust fan with at least 100 CFM.
+1 on the Panasonic fan. Pair it up with a timer.
As far as fan goes, get a Panasonic exhaust fan with at least 100 CFM.
+1 on the Panasonic fan. Pair it up with a timer.
This video was made for exactly this scenario: https://www.youtube.com/watch?v=PqrZWd_CQIE
I installed a bathroom fan roof vent...it was exactly as easy as it was in the video and takes the same amount of time to do as they did to explain it. Once it is done your fears are gone concerning moisture and bathroom ventilation.
I installed a bathroom fan roof vent...it was exactly as easy as it was in the video and takes the same amount of time to do as they did to explain it. Once it is done your fears are gone concerning moisture and bathroom ventilation.
I also recommend a Panasonic bath fan, and be sure to use smooth exhaust pipe, not the vinyl flex stuff that traps moisture in the webbing.
Originally Posted by PW01
Is it a good idea to "oversized" the fan? I'm looking at the Broan QT Series for both bathrooms. The hall bath is a bit over 60 sqft so I'm looking at the 80 cfm model, the master bath is about 100 sqft so I'm looking at a 150 cfm unit for it. Good or bad idea?
More CFM= more louder
Is it a good idea to "oversized" the fan? I'm looking at the Broan QT Series for both bathrooms. The hall bath is a bit over 60 sqft so I'm looking at the 80 cfm model, the master bath is about 100 sqft so I'm looking at a 150 cfm unit for it. Good or bad idea?
More CFM= more louder
Mine just vents into the attic, has been like that on all three houses I have owned. Each house also had the soffett just like shown on the video, but in addition, has two "whirlybirds" on the rooftop that pull up the air.
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