Exhaust fan roof caps leaking - Need new solution - Contractor Talk - Professional Construction and Remodeling Forum

f2contracting · 06-16-2009, 12:06 PM

I am having a problem with rain water coming in the roof caps for the bath exhaust fans. Heavy Texas thunderstorms blow in water, which runs down the pipe into the fan and ultimately into the ceiling damaging the drywall. Has anyone else had a problem like this? Do I need a different type of roof cap? I am attaching a photo of the one I'm using.

greghvacguy · 06-17-2009, 10:56 PM

There is a damper/flapper on it. sounds like it is not closing. I have one on my dryer and lint gets n it and stays open I clean it every 90 days and no leaks.

DuMass · 06-18-2009, 04:46 PM

I’ve installed a lot of those Nutone Scovill/Broan caps over the years.
One thing that comes to mind is roof pitch. If it’s a flat roof or has less than the manufacturers recommended minimum pitch, then water leakage like that can definitely happen.

neolitic · 06-18-2009, 05:46 PM

Is someone pushing the pipe
up so far that it holds the
damper open?

NickTech · 06-21-2009, 01:10 PM

with winds blowing the rain in i think a rubberized roof flashing with a 3 or 4 inch pvc leader and a gooseneck or tee termination would do. maybe coming up with a tee drip legg and drain system like in the old original black cpvc flue pipe system. goodluck