I need to vent a room in an uninsulated cabin - the ceiling is also the roof - so I don't need soffit tubing or anything like that. I am looking for a fairly cheap item that has a large cfm ability.
(This is for venting steam from a maple syrup evaporator)
We ended up just putting in two vents in the roof. (Maybe 12"x12" each - though maybe a little smaller than that)
We did not need a fan. We still get a tiny bit of condensation on the ceiling but not even close to what it was before. We are happy with the two vents but may add one more.
First we put in one vent and it was FAR superior to just having windows open. We could actually see across the room when boiling/evaporating. Then we put in a second vent and that made a difference too.
The next vent will be fed directly from a steam hood we will put over the evaporating pan.