Re: Dripping water down vent pipe
A couple of things come to mind .........
Is the penetration for the vent pipe into the attic well sealed?
This might be caused by condensation dripping down the vent stack
A good method would be use a can of spray foam to ensure a tight air seal around the vent pipe penetration into the attic. This will prevent warm moist air from rushing up the cavity into the cold attic and condensing.
The other thing would be if the connection for the PVC was made to a cast iron vent stack ...... the coupling connector might be leaking. This could also have condensation dripping back down form the warm air in the pipe condensing when it meets the colder attic.
Just a thought.
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