Attic gable vent sealing recommendation?

Old 07-11-22, 04:30 PM
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Attic gable vent sealing recommendation?

Hello, I rebuilt my gable vent bc it was rotted. I am wondering what is best method to

seal the frame around it so water does not get in?

Would silicone adhesive be good option? Or should some rubber gasket or sealing tape around the outer frame and between the siding be used?

I just fear silicone adhesive it would wear.

Anybody have any good suggestions for long life? I have attached picture of old frame/new frame.

Old 07-11-22, 10:14 PM
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Ideally it would get "Z" flashing installed under the siding at the top and over the vent, just like a window.
Old 07-12-22, 05:46 AM
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I agree. With all the complexities of the siding it will be difficult to caulk and not leak somewhere. I would remove the shingles around the opening. Then flash and install the vent as if it were new construction with the flashing being the key part. It is very important to get it behind the siding.
Old 07-12-22, 10:02 AM
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The reason it rotted the first time was water was present for extended periods of time. Flash it correctly to direct the water over and away it wont get wet and rot!
Old 07-12-22, 10:17 AM
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The picture shows the old one had a z flashing. I assume it's still there. The problem is that water runs off the ends of the z flashing, and it gets behind the siding and trim. To work properly, the ends of a z flashing need to be turned up.

If I was doing it, I'd replace the z flashing with one as described above, then cover any exposed sheathing with butyl window flashing tape while you have it exposed. When you put the new louver back in, caulk the sides with a paintable caulk. Any siding caulk will do. 100% silicone is not paintable. I'd probably use Vulkem 116.

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