Originally Posted by danster44
excellent observation -- I have DC (super quiet / energy efficient) wall exhaust fans, and they currently exhaust into the attic -- I really need to run these to an outside wall vent -- need to find one I like for metal building walls that has a good insect screen on it.
Venting into the attic is not a good idea because you are introducing humid/moist air into attic space. Ideally you want that air to exit through the roof or wall to the outside.
Like you, I don't want to have vents protruding through the roof of my home because of energy reasons and pest issues. Currently the home I am in now has bathroom vents and I get earwigs, crickets, roaches and all types of creepy crawlers that crawl in from the roof, down the vent, and into my home. I tried putting screens on the interior covers but they can still fit through the sides.
My solution will most likely be a ERV setup which brings in outside air, filters it and then distributes it throughout the home. This can eliminate the bathroom vent issue. Other than that, one would have to find a really good screened stack that doesn't let in pests from the roof.