Bathroom Vent unused causing moist attic?

[beagle150]

My home was recently inspected. The home inspector said that the bathroom fan which is vented into the attic adds pressure to the attic which in turn increases the moisture in the attic.

This particular bathroom fan has not been used ... no showers have ever been taken in that bathroom. I never thought venting a fan into the attic was a good idea and so haven't used the bathroom fan nor has anyone showered in that bathroom.

I will have the bathroom vented out through the roof as the roof needs to be torn off and replaced in the spring.

In the meantime, I am wondering if it would be helpful ... to keep the moisture / humidity level down in the attic to cover the bathroom vent opening.

Does this make sense?

[kurt]

I doubt that a few months is going to cause much lingering problem. It does get cold in Rochester, so you could have some condensation, though.

Why don't you take a few showers, pop the hatch, and see how it looks? You're not going to see anything horrible until it gets really cold out anyway.

You could also extend the fan discharge up to a roof vent w/some plastic ducting; this would only be temporary until you did the roof. While I don't condone this practice, I see it all the time, and I never see any problems related to it.

[Chad Fabry]

My home was recently inspected. The home inspector said that the bathroom fan which is vented into the attic adds pressure to the attic which in turn increases the moisture in the attic.

Pressure doesn't add moisture. Moisture adds moisture.

I'm from the Rochester area and ,believe it or not, even fans that don't get used leak enough air (and the water vapor in the air) to create significant issues.

The mold in the photo was caused by air leakage through a recessed light fixture. That's a much smaller hole in the ceiling than fan you're not using

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