Share 'Exhaust Fan Venting - Bathroom, ERV, & HRV'

In another thread (that grew quite unwieldy) the question came up about exhaust venting Robert Riversong:  "the most foolish way to duct an exhaust fan is straight up through the roof" John Brooks: "It seems to me that in a heating climate (or during the heating season)... It would be desirable to have the "passive NPP"  high. This would make the house more "negative" and would reduce (or elimina…