47WDXPW
Well-known member
Do these need to be vented to the out side (stack vent tie in ) or is it OK to let it blow into the attic area ? This is a bathroom with a shower.
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Bathroom exhaust fan
- Thread starter 47WDXPW
- Start date
James-W
Well-known member
It needs to be vented outside, NEVER exhaust it into the attic.
kwschumm
Well-known member
The reason for not venting in the attic is that the last thing you want up there is mold, fungus and rot. Vent it to the outdoors.
2level
Well-known member
I recommend that you do not do what the former owner of my house did: he tied the exhaust duct from one of the fart fans into a roof vent. Try to run the vent duct pipe/hose straight up, as bend-free as possible, with the proper vent hood.
trashmanssd
Well-known member
You could do what the idiot who built my house did 14 years ago and vent into the attic but you will get mold. I have owned 2 houses so far in my life and both had the bath fan vented in to the attic and I had both fixed and vented properly. Sold first house shortly after we did bathroom oer and found where vent was routed and had to pay 3K for mold remediation because of said vent. My asthma and allergies started when I lived in that house, do your self a favor and vent it outside properly.
engineer2
Well-known member
With a shower you might want something that is a least 100 cfm installed within 3ft of the shower stall or directly over it. Makeup air has to get into the room too (under the door or a heat/AC duct) or you will still have steamy mirrors. I've learned from experience.
Panasonic makes super quiet fans, but most other companies have them now too.
Panasonic makes super quiet fans, but most other companies have them now too.
ford33
Well-known member
Vent to exterior always.
Depending upon the age of the home and how tightly sealed it is, consider that a bath fan forces conditioned (heated or cooled) air out of the interior of the home. You will need to make up that exhausted air by allowing air to enter the home. I am not an expert on this but you should research how exterior air will enter the home when the bath fan runs.
You don't want to draw air into the home from the furnace or hot water heater flue. That would introduce carbon monoxide. Another source of air incoming air is the attic. If it is not sealed tight to the home interior you may be drawing attic air into the interior of the home. In the summer that means very hot air entering the home.
Depending upon the age of the home and how tightly sealed it is, consider that a bath fan forces conditioned (heated or cooled) air out of the interior of the home. You will need to make up that exhausted air by allowing air to enter the home. I am not an expert on this but you should research how exterior air will enter the home when the bath fan runs.
You don't want to draw air into the home from the furnace or hot water heater flue. That would introduce carbon monoxide. Another source of air incoming air is the attic. If it is not sealed tight to the home interior you may be drawing attic air into the interior of the home. In the summer that means very hot air entering the home.
Todd.Brock
Well-known member
I am remodeling my bathroom now. All the 30 year old vents from 2 bathrooms vented into the soffit. There was batts of insulation to block off the air coming back in the attic - I guess that was effective. I have run into the soffit until some other siding/soffit renovations are completed and then I will then through the soffit with a Spring loaded vent. I used the Panasonic fans. They are really big but super quiet. You can still hear them, but it’s a low tone that you don’t hear with the shower running.
Falcon67
Well-known member
I vent into the attic near one of the roof vents. I get real tired of making holes in the roof. The builder left the exhaust outlets under the insulation, so just running some pipe was an improvement. We're dry here, not a mold issue.
jeff_gates
Well-known member
because of our setup we went through the walls. I got this from Amazon:
Panasonic FV-11VQC5 WhisperSense 110 CFM Ceiling Mounted Ventilation Fan with Dual Sensor Motion and Humidity Technology
Hooded Wall Vent with Spring Loaded Damper, Gasket and Screen - Galvanized 4 inch
Dundas Jafine BPC425R6 Insulated Flexible Duct with Black Jacket, 4-Inches by 25-Feet
Panasonic FV-11VQC5 WhisperSense 110 CFM Ceiling Mounted Ventilation Fan with Dual Sensor Motion and Humidity Technology
Hooded Wall Vent with Spring Loaded Damper, Gasket and Screen - Galvanized 4 inch
Dundas Jafine BPC425R6 Insulated Flexible Duct with Black Jacket, 4-Inches by 25-Feet
engineer2
Well-known member
Anybody found any plastic wall vents that don't turn black and rot away after 5 years? They use really cheap plastic and weather really beats them up. Maybe I'll just switch to metal.
Wow I knew this was wrong (attic venting ) I didn't know how many things it affected thanks for the replies. So Im going to install one of the Panasonic models listed above so install the fan and run the duct to a new hole in the roof ? I have seen roofs with a 90* elbo on top of a vent line is this the right way to do it ?
2level
Well-known member
Wow I knew this was wrong (attic venting ) I didn't know how many things it affected thanks for the replies. So Im going to install one of the Panasonic models listed above so install the fan and run the duct to a new hole in the roof ? I have seen roofs with a 90* elbo on top of a vent line is this the right way to do it ?
Are you talking about the 90* turn built into a typical roof vent cap? If so, yes that's one way to go. Sometimes you go out the wall. What's access like; attic space, is there a 2nd story?
CitadelBlue
Well-known member
The reason for not venting in the attic is that the last thing you want up there is mold, fungus and rot. Vent it to the outdoors.
For some reason the builder of of house(we are the second owners) vented the bathroom vents into the attic about 6 inches from the ridge roof vent. Guess he figured the ridge roof would take care of the exhaust from the bathroom .....
Well... we are in northern VA near DC. It was Thanksgiving weekend and we had my daughter, her new husband and his parents cycle through the bathroom and shower . My daugher was th elast one to go through and noticed water dripping from the vent. I went into the attic and noticed the frost on the underside of the roof/plywood and condensation all over the metal exhaust vent.
My vent now runs between the attic joists in an insulated PVC 4 inch pipe and exits at the soffits via a vent opening. No more moisture/frost in the attic.