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patching galvanized duct

caseyr | Posted in Construction Techniques on

I need to put a patch over a 5″ hole in a galvanized duct that I will be using for the kitchen vent fan. Since I can’t find my pop riveter, I will be fastening the patch with sheet metal screws. Since I want this to be reasonably air tight, what is the best material to place under the patch to seal it. Is silicon sealant adequate for this (for the next 30+ years) or do I need to go with epoxy or something else?

Replies

  1. User avater
    user-246028 | | #1

    Aluminum foil tape will do the trick nicely.

    Dave

  2. WayneL5 | | #2

    The acid in the silicone will degrade the metal.  Use aluminum tape.

    1. DanH | | #3

      There is also the duct mastic -- might be good between the layers of metal.
      So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin

      1. caseyr | | #4

        Thanks folks, I think the duct mastic is what I will look for - in addition to the tape.

        1. User avater
          IMERC | | #5

          the mastic and mesh tate is the way to go..

          clean 1st denatured alcohol...Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->

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