[MandoMan]

My bathrooms each have a loud exhaust fan in the ceiling. I plan to replace these with very quiet ones. The residential building codes all require that these be ventilated to the outside, either through the wall or the roof. Ideally, that vent is solid metal going straight up from the fan, not plastic hose or corrugated metal pipe. However, when I look at my roof, I don’t see any openings for these vent pipes. I see the attic ventilators near the peak of the roof, and a dryer vent, and the small air vents required for the plumbing. That’s all.

Do you know where the air goes from these bathroom fans? Blowing this air into attics has been against the building code for decades. It’s a great way to soak the plywood above the vent, leading to rot.

Bathroom Vent Fan Codes, Installation, Inspection, Repairs

[dewilson58]

under the overhang of your roof hips (eaves)......about 3 inches.

[skip0358]

Yep it exhausts out through the soffit.

[Marathon Man]

Originally Posted by skip0358

Yep it exhausts out through the soffit.

... and into your neighbor's yard.

[ogme480]

I've found all three of my bath fans venting to the outside coming out beneath the soffit (eaves). Our dryer vent went straight up through the roof and is a galvanized looking vent you can see on the roof. Some fans (Broan) can have their "guts" only replaced with a kit from either Lowe's or Home Depot. Much like garbage disposals, they are sold with different "quiet" ratings and if the kits work, aren't much work and you don't have to fool with the existing framework and/or venting in place. This would apply to an existing fan & not a new install. Hope this helps.

[Accidental1]

It's my understanding that venting through the soffit isn't a great idea either. I believe the soffit tends to draw in outside air so if you vent your humid bathroom air out the soffit it just gets drawn back into your attic. I've had direct experience with this on our house in Indiana. The sheathing inside the attic directly above the soffit vent showed signs of mold so I had the vent re-routed through the roof.

[jeffy]

I have replaced many of these myself. The good thing is that they are very generic and each time I was able to purchase at local Lowe’s or Hone depot, just the noisey motor. Easy DIY. Takes only about ten minutes. Look up on YouTube if you want to try it. Replacement of the whole unit is a bear.

[MandoMan]

Originally Posted by ogme480

I've found all three of my bath fans venting to the outside coming out beneath the soffit (eaves). Our dryer vent went straight up through the roof and is a galvanized looking vent you can see on the roof. Some fans (Broan) can have their "guts" only replaced with a kit from either Lowe's or Home Depot. Much like garbage disposals, they are sold with different "quiet" ratings and if the kits work, aren't much work and you don't have to fool with the existing framework and/or venting in place. This would apply to an existing fan & not a new install. Hope this helps.

Thanks very much! I’ll look into that. Replacing the motor is probably something I can do myself. I replaced two ceiling fans and four light switches yesterday.

[MandoMan]

Originally Posted by Accidental1

It's my understanding that venting through the soffit isn't a great idea either. I believe the soffit tends to draw in outside air so if you vent your humid bathroom air out the soffit it just gets drawn back into your attic. I've had direct experience with this on our house in Indiana. The sheathing inside the attic directly above the soffit vent showed signs of mold so I had the vent re-routed through the roof.

I’ve vented ceiling fans through the soffit before, but always with a hole in the soffit letting out the expelled air. You are right that just blowing it into the soffit space could cause a moisture buildup, but of course it is blowing air that is 40-50% humidity, unless it is venting after a shower, while the air being sucked through the soffit into the attic is often 80% humidity and sometimes more.

Yesterday I went up to my attic for the first time. I discovered that the soffit vents are working well all around the garage, but they seem to be blocked by insulation around the rest of the house. However, it may be that the air through the garage soffits are enough to maintain air circulation in the attic, what with two air vents at the top of the roof and a fan with solar panels on top of it.

I also discovered that workers over the years have pushed away the insulation over the bottom chords of many of the roof trusses, leaving them exposed. There seems to be, at present, at most six inches of insulation, with only four inches of wood where the trusses are. (In the home I built in Pennsylvania, I had 16” of blown-in virgin fiberglass.) I suspect that adding more might decrease cooling costs, though the payback may be several years.

Thanks for the info about the venting.

[greenflash245]

it goes out of the bathroom

[Kgcetm]

Guest bedroom?

[NoMoSno]

Originally Posted by Choro&Swing

My bathrooms each have a loud exhaust fan in the ceiling. I plan to replace these with very quiet ones. The residential building codes all require that these be ventilated to the outside, either through the wall or the roof. Ideally, that vent is solid metal going straight up from the fan, not plastic hose or corrugated metal pipe. However, when I look at my roof, I don’t see any openings for these vent pipes. I see the attic ventilators near the peak of the roof, and a dryer vent, and the small air vents required for the plumbing. That’s all.

Do you know where the air goes from these bathroom fans? Blowing this air into attics has been against the building code for decades. It’s a great way to soak the plywood above the vent, leading to rot.

Bathroom Vent Fan Codes, Installation, Inspection, Repairs

You will find FL codes lagged behind many other states.
I have a few FL homes built in the early 90's where the vent hose terminates under the ridge vent. Which was allowed at the time, confirmed with the county inspector on his last visit.
Also, note each FL county can have their own unique codes.

[davephan]

Another thing you can do is to replace the bathroom fan switch with a timer switch. Then the bathroom fan automatically shuts off. I never see the bathroom fan switches when looking at other houses, my extended family, friends, and when house hunting real estate. I installed the bathroom fan timer switches in all my bathrooms. It increases the quality of your life, and it’s a cheap, quick, and simple home improvement project.

Another thing that will improve your bathroom is to change the light switches with occupancy light switches. Then when you enter the bathroom, the light turns on automatically without manually having to turn on the light switch, and manually having to turn off the light switch, since the light turns off automatically after you leave the bathroom. That home improvement is also quick, cheap, and improves your quality of life. But almost everyone still uses the old fashioned manual light switches.

Another home improvement you can do to your bathroom is to modify your shower head. My brother in law did that to his water flow constricting shower heads by drilling the water flow constricting part inside the shower head. That makes taking a shower much more pleasant with much more water flow. Of course, your shower uses more water, but water doesn’t cost much compared to improving your experience of better showers.

These are three things that you can easily do to improve your bathrooms, that almost no one does. We just bought a home in Florida, after house hunting for several years. I’m going to do all those improvements to each bathroom right away after we close on the house.

[Topspinmo]

I would imagine the older sardine style construction they just vent into the attics.

[flhr95]

Originally Posted by Choro&Swing

I’ve vented ceiling fans through the soffit before, but always with a hole in the soffit letting out the expelled air. You are right that just blowing it into the soffit space could cause a moisture buildup, but of course it is blowing air that is 40-50% humidity, unless it is venting after a shower, while the air being sucked through the soffit into the attic is often 80% humidity and sometimes more.

Yesterday I went up to my attic for the first time. I discovered that the soffit vents are working well all around the garage, but they seem to be blocked by insulation around the rest of the house. However, it may be that the air through the garage soffits are enough to maintain air circulation in the attic, what with two air vents at the top of the roof and a fan with solar panels on top of it.

I also discovered that workers over the years have pushed away the insulation over the bottom chords of many of the roof trusses, leaving them exposed. There seems to be, at present, at most six inches of insulation, with only four inches of wood where the trusses are. (In the home I built in Pennsylvania, I had 16” of blown-in virgin fiberglass.) I suspect that adding more might decrease cooling costs, though the payback may be several years.

Thanks for the info about the venting.

We used Munn's AC to blow in insulation over our garage and lanai, very reasonable and polite.