Louvered Roof Vents Leaking

Location west Central Florida, re-roof done by local licensed contractor. Louvered fixed vents on a hip roof. The roof vents were installed without the flange exposed at the bottom? Architectural asphalt shingles.

6 Months after the 5 year warranty expired during recent storm, ceiling staining and ceiling fan globe filled with water.

Water flows down between the vents and enters below the shingles. (See photos.) I am not a contractor but i don’t see how this can be an acceptable method of installation, seems to go against basic roof principles, water enters needs to flow back onto the roof. This active leak just became noticeable after all these years.

From visual observation, most new re-roofs in my area have the same install method for all roof penetrations. Maybe a single vent if cut close and sealed? But this double passive air vent?

Called the “reputable roofing co” Their first response, out of warranty, so sorry.

Any advice will be appreciated on how to proceed with this, which is now an active leak causing damage. I suspect if they will offer anything

It’s code in Florida to apply roof cement around all penetration, they cover up the bottom flange to hide it. Also, those lomanco 750 vents aren’t really meant to be that close together, should be far enough apart to run a 6in wide shingle between them. You will have to find and pay somebody to fix it.

There was a couple years around here where builders were buying these as a lower price alternative to more ezpensive bigger box vents.

They are are actually made together like this.

Yes, even though we are required to cement around the top and outer sides.
The bottom flange shouldnt.

So now it is trapping water

1 Like

If those are 2 separate vents,thats likely the issue.
There is a double vent made for spots like that and should have been used.

Yes, they are two seperate vents.
But made together by the same manufacturer.
They hemmed the vents together.

I agree with everyone else. These look like lomanco 770 vents. I think if you seal the rivet, on the bottom and caulk them or Florida black asphalt, they shouldn’t cause a problem. I’ve seen this setup, but never bought them. I use the 750. I believe your leak is because the shingle covering the bottom flange is causing a damn.
Pull it off, buy a new one and install it according to the lomanco instructions, using Florida code.

It’s leaking at the joint where the two shingles but together, at the bottom of the vents
in the middle, second course down.

Thanks for the replies. These are Lemanco 770D’s which are doubles. See the photo of the center between the two vents, it’s obvious the water is channeled straight down the center and entering under the shingles and has no where to exit because of this install. This can’t be correctly installed, just common sense. I have a double installed on south and north side and 4 along the back facing east. Two are actively leaking. Even if seal now, water will eventually get in here.