I am wondering about the correct orientation of duct work for ceiling bath fans and a dryer in a new house. Our HRV guy installed them with the male (crimped) ends pointing to the exterior, so that it would seem that any condensation running down the inside of the duct will tend to want to leak through the joints. Am I right to be concerned about this, or is it not much of an issue? We live in a cold climate (AK) and it seems like it would be common sense to do it the other way, to avoid potential leaks.
Thanks-
Replies
That's definitely the correct direction for the dryer vent. If you turn the crimp toward the dryer, lint will catch on it and quickly clog the pipe.
Where do the bath fan vents exit the house?
http://www.quittintime.com/ View Image
Thanks, that makes sense for the dryer; how about the bath fans?
The bath fans ducts should slope downward, especially in your climate so the crimp should also face the outside so any condensation drips outside rather than inside.
But, there is a loop detail similar to a drain trap that's used if the duct goes thru the roof. I'm unclear on which way the crimp would run with that detail. http://www.quittintime.com/ View Image
1) Orientation is correct. 2) Ideally, the ducts are running through conditioned space so there should't be much condensation happening. 3) Horizontal runs should be pitched towards the exterior as well so any condensation that does occur will be towards the outside. 4) Lastly, joints should also be taped with foil tape so they can't leak.