? about venting bathroom exhaust fan

14 years ago

I just had my house resided. Unfortunately the installer covered up the opening for the 2 bathroom exhaust fans with soffit. The owner of the business wants to replace the soffit with the vented type and he says that will work. Doesn't sound right to me. I had a hole cut in the soffit so the air was vented directly to the outside before.

Shouldn't that hot air be directly vented outside? And what about winter when that moisture inside the soffit freezes?

Thanks for any help you can give. The owner is coming tomorrow, Monday, to 'fix' the problem.

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monicakm_gw
14 years ago
I'm not an expert, but from what I've read, you're right, that's not going to be enough. If you haven't already, why don't you ask on some of the GW building forums also to improve your chances of getting this answered before the contractor gets there tomorrow :)
Here is some info I've saved from our master bath remodel. Hope you find it helpful. If not, maybe someone else will :)
Monica
Venting exhaust
If he is venting the exhaust into the attic air space, that's bad. Even if there are attic vents (normally gable wall louvered vent panels, or a combination of soffit and ridge vents) in the attic that allow air to move through the space.

If he has the end of the duct just pointing at the attic gable vent, that's no good either. The goal is to get the moist air outside the house, not to dump it directly in the attic, or dump it near the gable vent, where air currents can keep the moist air in the attic.

If he is bringing the duct up into the attic, then continuing the duct laterally and running the duct out through the gable wall and installing a vent cap out there, then that's a good thing.

I prefer the vent to be rigid metal instead of the flex duct, and I prefer the lateral run to be sloped slightly lower as it runs towards the gable wall. I use aluminum tape to tape all seams in the duct, taping both the seam that runs the length of each piece of duct as well as around the circumference where two pieces are joined together. This way if there is any condensate in the duct it runs out the vent instead of pooling and/or running back down into the fan.

It's a small, but important detail.

Personally, I prefer as few holes in the roof as possible.

Mongo

Rigid ducts are fairly easy to slope, they just need periodic support along the horizontal run. In a attic it can either be hangers coming down off the rafters, or wood scabbed to the floor joists running up vertically.

Oooooh. I didn't think of a brick house. Brick can be more difficult, but it is done. Still with brick, it might actually be easier to go out the roof, but hopefully only if it's on the back side of the house.

I'm not certain if venting to the outside is required by code in your area, you could give your local building department a call. If it is a code requirement (it is in my locale), then it should have been included in the scope of the work. After all, he should bid the job and complete it to code, right?

Then again, I wouldn't want a ticked off contractor cutting a hole in my brick wall or in my roof while angry and while trying to do it on the cheap.
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? about venting bathroom exhaust fan

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monicakm_gw

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