Combine 2 bath exhaust fan runs to vent outside?
I have 2 bathrooms, each with a fan. Both come into the attic as flexible metal about 3 feet from each other. They then snake around and go down to a soffit.
I realize from reaching on this site that this isn’t ideal. I’m considering switching them to rigid metal or pvc once they reach the attic, have each continue up slightly about a foot above the attic floor, then slope down toward a new vent in a gable wall.
Since they are so close to each other I’m hoping it would be acceptable to combine them into a 4x4x4 Y fitting before the approx. 8 foot run to the gable wall. I guess I could also switch it to a 4x4x6 Y if I could find the vent for in the gable wall in a 6″ size.
If this would be ok I’d like to switch the duct to PVC as the fitting is more widely available.
The vent would come out in this photo, at approx. where a line down straight down from the highest roof point and over from the original roof’s highest point meet.
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