Go through the roof.
Properly installed, the roof vent will be no issue at all.
The moisture laden air simply moves away, into the atmosphere.

Coming out of the soffits, you are pumping it down, where it now wants to rise. Back into the soffit.

Protrusions through the roof? Well you have the vents for your plumbing, at least two I'd expect. A chimney comes either through or alongside. Your roof vents or ridge vent also are there.

What is one more, if they are all installed and flashed and such properly?

If the roof pitch is low I would vote for the soffit if there is no eave vent nearby.

No offense, drywall diy guy, but roofing cement is the last thing you want on a roof vent. It holds water in, you want it to drain away.

Installed correctly there is no need for any cement, caulk, goop, whatever.

On a roof, its not if its going to leak, it is when its going to leak. You don't want to hasten that happening. Let it drain.

For the best results, the vent should terminate through a gable wall of the roof assembly for best results.

Vent terminations through roofs or soffits should be avoided whenever possible.

The video I watched when I did this is at the link below. I used the roof cement over the exposed nails. The video recommended caulk however.

Here is a link that might be useful: Bathroom Roof Vent

For the best results, the vent should terminate through a gable wall of the roof assembly...

Again, no offense meant but "best" results would be a continuous ridge vent, no? Vents placed on gable ends don't work very well unless they are powered.

And a proper roof vent doesn't require any visible nails.
Stop buying them off the shelf at a big box store and go to a proper roofing supply, spend a couple of dollars more for the right stuff. Its no wonder folks complain about leaky roofs all the time!

And while I'm at it (lol), venting a roof is a lot more than slapping some vents into the roof, you really should calculate soffit area, attic volume, etc. I bet only one in ten roofers know how and of those I bet only one in ten actually does it.

The difference in a standard, stick built home with and without properly spec'd and sized AND installed roof venting is huge.

Roof keeps everything else dry, roof venting keeps everything else livable. And makes your roof last longer. My advice to the OP is do it right, find a someone in real life who will do the calculations, fix the soffits, the baffled airway, the ratio of soffit to vent space, install the proper vents in the proper manner (hint: they won't be plastic) and willingly help you become aware of the how and why.

Or not.

"Again, no offense meant but "best" results would be a continuous ridge vent, no? Vents placed on gable ends don't work very well unless they are powered."

Huh?

We are talking about bath fan vent termination locations, not attic vent locations....

So right, sorry, my mind switched from bath fan to just roof vents in general.

A powered gable vent, venting a bath or kitchen fan would be just fine.

Oh no!!..lets not do the pav thing!
not again

Whichever way you decide, make sure the vent fan has enough HP to actually vent the air. If the line run is long and you have a small unit, it won't vent properly, especially if you go straight up through the roof and you have big attic. I wouldn't assume whoever's doing this for you calculates it right. Also, unless you specify, you're probably going to get the cheapest fan the guy can get.

FWIW, I recently replaced both my bath fans with Panasonic units. These are expensive, but they are good quality and very quiet.

The Panasonic is actually what I bought. I am going to have the roofer install the vent outlet directly overhead.

Thanks for the replies!

David

Never vent through a soffit. This is common sense/roofing 101. Anyone who tells you different is either a fool or a liar.

If you push warm/humid air through the soffit, it will just get sucked back into the attic and lead to other problems like mildew. Going through the roof guarantees it will go up in the air and away from your home.

When I put in a new exhaust fan in our bathroom the builder never put any exhaust to the roof. It was just venting into the attic. (Florida home)- 30 years!. I did not want to punch a hole into the roof so I ran the exhaust over to the soffit and installed it there with a vent. HD and Lowes sell soffit vents. To me, I did not want another hole in my roof but to each their own.

Panasonic install directions are clear that their exhaust fans (at least my Whisper Warm) are to be vented out the roof. I gave the instructions to my Solatube guy and while he was installing the tubes he vented my Panasonic for me. There must be a reason that Panasonic advises this. They don't provide any parts for it so it's not like they are making money on what type of method they are recommending.

Which ever is the shortest run.

I have to chime in here for some advice for my upcoming bathroom reno.. I will be taking a "shower room" and "half bath" to two full baths.

I have a hip roof, 2 story colonial style home. Currently there is no venting as there has been no "real" updates done. The multiple prior owners did some not so great redecorating etc but never installed exhaust or plumbing vents.

As I will have all of the walls open, I am planning on fixing this. My problem lies in that I've spoken to several carpenters - all differ in what to do. Two turned down the job based on the height and pitch of the roof, stating that they did "not want to be up that high" - granted the roof is quite high - equiv to a 3 story due to the basement being a walk out etc.

So the two that agreed to take the job (havent decided on either one yet) say to vent to the soffit - given my roof there is plenty of overhang. I also live in Maine - my roof spends the winter fully covered in snow.

please advise....

lostinit - why get insulting?

The relocation company that bought my house for a move with a Fortune500 company required me to vent my fan through the soffit. Because it is building code in some cities, I had to meet their "uniform standard" of strictest standards. Therefore, if it is building code in some places, it must not be common sense 101. Their explanation, because vented through the roof results in leaks.

qc, this is a really old thread - lostinit might not see your reply.

I'm afraid I agree with him/her, however. The explanation was included in the post: "If you push warm/humid air through the soffit, it will just get sucked back into the attic and lead to other problems like mildew. Going through the roof guarantees it will go up in the air and away from your home."

I would love to see a copy of the building code that suggests venting a bathroom fan through the soffit is recommended.

The alternative to a roof exhaust (if you're concerned about not being able to seal the hole in the roof) is to exhaust through a gable end. Just make sure that there is a slight slope to the outside, so and condensation in the duct will end up outside. And, as someone else pointed out, make sure the fan is powerful enough to do the job. Longer runs require more power.

So I'm replacing my un-insulated vent tubing with insulated because i live in wisconsin and it condenses and drips through ceiling, comes out in low areas at seems of tubing because it goes across attic a distance of 15 - 18 feet on a curve with multiple low spots. I present have a sled under the seem to collect water from last winter tabokkal ! Choice is go up to roof 5-6 feet or out the present vent 15-18 feet with insulated pipe Or shorten the line by going straight to side of home but this requires going up high with latter to drill a new vent hole, as tight quarters in attic prevent drilling from attic. Going to the soffet is 12 feet. I was considering soffet only because I was fearful of too much slow covering my vent. Do I have a legitimate concern as sometimes roof is covered with 10 to 12 inches? My pitch is lower 12-18 I think thats right. Is there a certain vent style or type recommendation? Is there a height that is recommended for safety and efficiency with going up to roof? Thanks for any advice I'll wait patiently

Roof or through a gable sidewall. Venting at the soffit is a bad idea.

if you had to go 15 feet to horizontal to gable or 5-6 feet up through roof what would you say is best option when it comes to best flow

Flow isn't as much of an issue as having the vent in a big and cold space where it can form condensation inside of it. If the fan is sized properly, it will move enough air. Most times, if we are going through a gable end wall, we lay them on the floor and insulate over the top of them so that they are inside the insulated space and therefore stay warm.

You always need to run them for a decent bit after the moisture has cleared to make sure that they are clear of any moisture inside the piping.

Wrap the section that is above the insulation with insulation to keep it warm as well.

Just installed a new fan in my master bath. There is a guest bath about 8-10 feet away, that was being vented into the attic. I would like to run them out at the same point. I was originally thinking of going through the roof, but the soffit vent I purchased has a flapper that would prevent the moisture from coming back in(I think?). Would it be ok to vent them through the soffit in this case? I'm trying to avoid putting a hole in the roof considering the time of year in NE Ohio, never know when the blizzard is coming. Thank you in advance

If you have a vented soffit, you don't want to use a soffit vent because the warm, moist air can be drawn back into the attic space.