Fans in apartments don't vent outside.

[Steve Ehrman]

We have an 8 unit apartment building. Although we have owned it for 4 years, we just realized that the bathroom and kitchen fans don't vent outside the building. They vent under the roof.

We are in the Detroit MI area. Should we be concerned with moisture and mold because of this? Could the roof be damaged?

[Steve K.]

 I had this issue in a quad and we stubbed each vent out through the roof, pretty simple fix but unfortunately it was too late for the decking which had deteriorated and started sagging thanks to too many years of too much moisture being trapped in there with inadequate venting. We had to replace the roof and vent everything properly plus replace some of the insulation. I'd vent those fart fans to the outside asap, and check your attic for mold as well as inspect the roof, decking and trusses/rafters for moisture damage/ premature decomposition. Chances are the attic space isn't vented properly as well so you may want to look into adding soffit vents and ridge vents while you're at it.