Patch Hole in Ductwork

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Posts: 11
Joined: Mon Mar 24, 2014 6:24 pm

Sat Apr 05, 2014 6:48 pm

heat duct.JPG
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I was thinking about opening up the top of the duct some more so I could get my hands into it to patch the bottom and side. Then put a separate patch on top. Maybe use pop rivets and tin, and apply some type of sealant over it. What type of sealant would work. Somebody had tried to to locate a toilet here. I found it when redoing the bathroom floor area. They did a nice number on the joist also. Thanks.


Posts: 385
Joined: Wed Apr 07, 2010 10:07 am

Sun Apr 06, 2014 12:34 am

Since the outside of the duct is probably cleaner than the inside here's a simple fix. Cut another piece of either sheet aluminum or metal larger than the hole. Apply a liberal bead of 100% silicone sealant to the mating surface. Place over the hole and use some metallic duct tape to hold it in place. The sealant will keep it all together once it cures.

Posts: 342
Joined: Fri Apr 06, 2007 9:14 am
Location: Delaware

Sun Apr 06, 2014 2:32 pm

Make yourself some aluminum patch pieces about two to three inches wider then the hole, then zip screw the patch on to the duct then cover that with aluminum tape. Do not use regular "Duct / Duck" tape. that is not for Ductwork. Also use aluminum for the patch because mixing metals causes corrosion. You can also get mastic that is made to seal ducts that you just trowel on the seams after you screw the patch down.

Tape: ... /100048600

Mastic: ... /100396973

Screws: ... /100137289


Posts: 11
Joined: Mon Mar 24, 2014 6:24 pm

Sun Apr 06, 2014 6:51 pm

Thanks for the replies.