We are getting a roof put on our house. The previous owner did not have the vent to the outside, just into the attic. We have not used the fan due to this and now is as best of time as ever to have one installed.

My question is that in our part of the country we see snow, sometimes feet at a shot. Should I be looking for a taller vent so it doesn't get blocked by accumulating snow or will a lower profile vent work just fine? Or will using the fan to exhaust humidity melt the snow and keep it clear? Am I overthinking this and just go with whatever that has a flapper and screen inside? Thank you.

I think ours is a square snorkel box with a built in critter cage. Maybe 4” tall and never had an issue with snow even when completely covered.

Mine are vented into the attic which is fine since we never really use them. Home inspector said they should be vented out through the soffit.

quote:

Originally posted by Oz_Shadow:
I think ours is a square snorkel box with a built in critter cage. Maybe 4” tall and never had an issue with snow even when completely covered.

This is what we use as well although we don’t get as much snow as you do in PA I would think it will be fine.
I will suggest that if you have to replace the “hose” consider getting an insulated 6” line as it will allow the fan to work much better, even if you have to use an adapter.

Never vent a fan into the attic unless you want to increase your chances of getting mold up there..

We don't often get "feet at a shot" of snow where I am in S.E. Michigan, but we do get snow, and sometimes close to a couple feet at a shot.

I installed this roof vent for our inside bathroom nearly 28 years ago:



Never had any problems with it, and that's on the side of the roof that gets the most accumulation.

When the home was re-roofed three-four years ago the roofers said it was just fine and put it back.

quote:

Originally posted by Scurvy:
Mine are vented into the attic which is fine since we never really use them.

I would argue it's not fine, being as, running or not, the warmest, moistest air in the home is running through that fan and into the attic crawl space.

quote:

Originally posted by Scurvy:
Home inspector said they should be vented out through the soffit.

Or through the roof. The home inspector was correct.

I was appalled when I found the original owner of our home had vented that bathroom's fan into the attic crawl space. Fixing that was one of my first orders of business after we moved in.

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Originally posted by smlsig:
Never vent a fan into the attic unless you want to increase your chances of getting mold up there..

Mold, as well as roof sheathing delamination and rot, which will eventually lead to roof failure.

Thanks all. I can spend half the price now and pick it up at the store instead of shipping one in. I am going with a 6" as the fan recommends it for flow and quietness. Insulated ducting as well as I have been doing my homework on this. I just wasn't sure about the height above the roof I should go.

Oh. Also if you vent it out of the soffit, make sure your attic doesn't draw air in through the soffit. It will pull the moist and right back in and defeat the purpose.

Personally I've never understood venting warm, humid air into an attic. Then again, as soon as I see a 6 sqft window in the shower I realize the designer is either a jackass or has binoculars pointed at that window when my wife/ daughter are there.

My roofer told me that up until not that long ago, bathroom exhaust venting into the attic was allowed under code.

It was changed in the mid/late 2000s (IIRC) to where new construction is now required to be vented to the exterior, but there are apparently many homes that are older than 15ish years old that still vent into the attic.

quote:

Originally posted by RogueJSK:
My roofer told me that up until not that long ago, bathroom exhaust venting into the attic was allowed under code.

It was changed in the mid/late 2000s (IIRC) to where new construction is now required to be vented to the exterior, but there are apparently many homes that are older than 15ish years old that still vent into the attic.

I think this is true as I've seen many ceiling bathroom vents that didn't have a provision for a hose.

Here in South Florida we prefer to have the vent exit the soffit. You may want to consider that as you don't have to worry about snow.

I can't vent through the soffit as our attic draws in from them all around. We have overhangs on all four sides.

quote:

Originally posted by RogueJSK:
My roofer told me that up until not that long ago, bathroom exhaust venting into the attic was allowed under code.

It was changed in the mid/late 2000s (IIRC) to where new construction is now required to be vented to the exterior, but there are apparently many homes that are older than 15ish years old that still vent into the attic.

Well prior to that. They used to let you vent to ridge vent, soffit vent, or gable vent, but never directly into the attic space. You are probably thinking of venting to a opening vs venting out the roof or side of the house.

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Originally posted by Skins2881:
You are probably thinking of venting to a opening vs venting out the roof or side of the house.

Maybe. Half of ours vent out the roof and the others vent out the soffit.

quote:

Originally posted by petr:
I can't vent through the soffit as our attic draws in from them all around. We have overhangs on all four sides.

In Florida (I don't know about other places) the discharge is in the soffit (which is the underhang of the roof). It is it's own vent and usually with a mess screen/cover. You're thinking of a soffit vent. The entire underhang of the roof is the soffit. Venting bathroom to the attic is frowned upon because the excess humidity can create mold and other issues.

The discharge is on the ridge of your roof or vents towards the peak. Hot air rises naturally and vents out the top while drawing cooler outside air in through your vented soffit.

quote:

Originally posted by LS1 GTO:
Personally I've never understood venting warm, humid air into an attic. Then again, as soon as I see a 6 sqft window in the shower I realize the designer is either a jackass or has binoculars pointed at that window when my wife/ daughter are there.

I love bathroom windows. Wouldn't dare have a bathroom without one if I can help it.

Sunshine, fresh air, venting, nature, etc. Not having a bathroom window sounds torturous.

quote:

Originally posted by petr:
The discharge is on the ridge of your roof or vents towards the peak. Hot air rises naturally and vents out the top.

Except what happens as that warm, moist air spreads out and rises is that it cools. As it cools, the temperature falls below the air's dew point and it sheds moisture--into the attic crawl space. The resulting moisture promotes mold growth and structural damage. That's why we don't do it that way any more and building code prohibits doing so in new construction.

Just like with the vent for your drains... I can't figure out why most vents terminate through roofs when it is not that hard to vent them out the side of the house or under the eave..

quote:

Originally posted by Blume9mm:
Just like with the vent for your drains... I can't figure out why most vents terminate through roofs when it is not that hard to vent them out the side of the house or under the eave..

For the same reasons you can't sidewall vent an atmospheric vented furnace. It will not draft correctly.
And who wants to smell sewer gas?